Steering device

ABSTRACT

A steering device includes a steering column (4a), a support bracket (17a) attachable to a vehicle body to support the steering column, and a tightening mechanism (80). The steering column includes an outer column (11a) and an inner column (10a) partially enclosed by the outer column (11a). The tightening mechanism has a first state in which the steering column is tightened with the support bracket and a second state in which the tightening is released. The outer column includes a first surface (49a) and a second surface (49b) arranged spaced apart from each other in a first direction, which intersects an axial direction, and such that the first surface and the second surface is pressed by the support bracket in the first state, and includes a clamp part (38). The clamp part has a third surface (40) provided independently from the first surface and the second surface and such that the third surface is pressed by the support bracket in the first state.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No.PCT/JP2016/064801, filed May 18, 2016, claiming priorities based onJapanese Patent Application No. 2015-102171, filed May 19, 2015,Japanese Patent Application No. 2015-203674, filed Oct. 15, 2015, andJapanese Patent Application No. 2015-207039, filed Oct. 21, 2015, thecontents of all of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present invention relates to a steering device including a positionadjusting mechanism which enables adjustment of a position of a steeringwheel in accordance with a physique and a driving posture of a driver.

TECHNICAL BACKGROUND

A steering device is configured to transmit movement of a steering wheel1 to a steering gear unit via a steering shaft 2 and give a steeringangle to right and left steering wheels 3 as shown in FIG. 45. Thesteering gear unit is configured to displace (push and pull) a tie rod 6on the basis of rotation of the steering shaft 2. As such a steeringdevice, a steering device which enables adjustment of a position of thesteering wheel 1 in accordance with a physique and a driving posture ofa driver is conventionally known.

RELATED ART DOCUMENTS Patent Document

Patent Document 1:

Japanese Patent Application, Publication No. 2014-104871

Patent Document 2:

Japanese Patent Application, Publication No. 2008-265646

Patent Document 3:

Japanese Patent Application, Publication No. 2008-114788

Patent Document 4:

Japanese Patent Application, Publication No. 2007-223383

Patent Document 5:

Japanese Patent Application, Publication No. 2002-104205

SUMMARY OF INVENTION Technical Problem

Compactification and weight reduction of a steering device including aposition adjusting mechanism are required, and high stability thereof isrequired.

An objective of an aspect of the present invention is to provide asteering device including a position adjusting mechanism with highstability.

Solution to Problem

A steering device according to an aspect of the present inventionincludes: a steering column including an outer column and an innercolumn, a part of the inner column being enclosed by the outer column; asupport bracket attachable to a vehicle body to support the steeringcolumn; and a tightening mechanism having a first state in which thesteering column is tightened with the support bracket and a second statein which the tightening is released. The outer column includes a firstsurface and a second surface arranged spaced apart from each other in afirst direction which intersects an axial direction, and such that thefirst surface and the second surface are pressed by the support bracketin the first state, and a clamp part having a third surface, the thirdsurface being provided independently from the first surface and thesecond surface, and such that the third surface is pressed by thesupport bracket in the first state.

A steering device according to another aspect of the present inventionincludes: a steering column having a configuration in which a frontsection of an outer column is set with respect to a rear section of aninner column so that a relative displacement therebetween can be appliedin an axial direction, the inner column being arranged at a relativelyfront side, the outer column being arranged at a relatively rear side; asupport bracket including a pair of support plates which sandwich thefront section of the outer column from both sides thereof in a widthdirection, the support bracket being installable on a vehicle body; andan adjusting rod inserted through a first through hole formed in thefront section of the outer column and second through holes formed in thesupport plates in the width direction. A Slit is formed in the frontsection of the outer column and extends at least in the axial directionof the outer column. A pair of clamp parts are provided adjacent to theslit, respectively, in a circumferential direction and arranged onportions on both of the sides of the outer column in the width directionsuch that the clamp parts are bent when an interval between innersurfaces of the support plates is reduced to elastically sandwich anouter circumferential surface of the inner column. A pair of actingsurfaces are provided on both lateral surfaces of the outer column inthe width direction and are spaced apart from each other in a verticaldirection such that each of the clamp parts is arranged therebetween,and such that torque acting on the outer column via the acting surfacesis transmitted to inner surfaces of the support plates.

Advantageous Effects of Invention

According to an aspect of the present invention, a steering deviceincluding a position adjusting mechanism with high stability isprovided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a steering device illustrating a first exampleaccording to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along line A-O-O-A ofFIG. 1.

FIG. 3 is a perspective view of a steering column.

FIG. 4 is a perspective view of the steering column viewed from anotherangle.

FIG. 5 is a side view of the steering column.

FIG. 6 is an end view of the steering column viewed from the left sideof FIG. 5.

FIG. 7 is an end view of the steering column from the right side of FIG.5.

FIG. 8 is an enlarged cross-sectional view taken along line B-B of FIG.5.

FIG. 9 is an enlarged cross-sectional view taken along line C-C of FIG.5.

FIG. 10 is a cross-sectional view taken along line D-D of FIG. 7.

FIG. 11 is a perspective view showing an outer column.

FIG. 12 is a side view of the outer column.

FIG. 13 is an end view of the outer column viewed from the left side ofFIG. 12.

FIG. 14 is an end view of the outer column viewed from the right side ofFIG. 12.

FIG. 15 is a bottom view of the outer column viewed from the bottom sideof FIG. 12.

FIG. 16 is an enlarged cross-sectional view taken along line E-E of FIG.12.

FIG. 17 is a cross-sectional view taken along with line F-F of FIG. 14.

FIG. 18 is a perspective view showing a pair of right and left rollers.

FIG. 19 is a front view of one roller.

FIG. 20 is a cross-sectional view taken along line G-G of FIG. 19.

FIG. 21 is a perspective view showing a collar.

FIG. 22 is a front view of the collar.

FIG. 23 is a cross-sectional view taken along line H-H of FIG. 22.

FIG. 24 is a perspective view showing a slide member.

FIG. 25 shows the slide member; part (A) is a front view, part (B) is arear view, part (C) is a side view, and part (D) is a cross-sectionalview of line I-I of part (A).

FIG. 26 is a side view of a steering column illustrating a secondexample according to an embodiment of the present invention.

FIG. 27 is an enlarged cross-sectional view of the steering column.

FIG. 28 is a side view of a steering device illustrating a third exampleaccording to an embodiment of the present invention.

FIG. 29 is an enlarged cross-sectional view taken along line A-O-O-A ofFIG. 28.

FIG. 30 is a perspective view of an outer column and an upper bracketviewed from the rear and below.

FIG. 31 is a perspective view of the outer column and the upper bracketviewed from the rear and above.

FIG. 32 is a perspective view of the outer column viewed from the rearand above.

FIG. 33 is a side view of the outer column viewed from one side in awidth direction.

FIG. 34 is a side view of the outer column viewed from the other side inthe width direction.

FIG. 35 is a bottom view of FIG. 33 when viewed from below.

FIG. 36 is a cross-sectional view taken along line B-B of FIG. 34.

FIG. 37 is a cross-sectional view taken along line C-C of FIG. 34.

FIG. 38 is a cross-sectional view taken along line D-D of FIG. 34.

FIG. 39 is a perspective view of a steering column illustrating a fourthexample according to an embodiment of the present invention.

FIG. 40 is a side view of an outer column.

FIG. 41 is a perspective view of a steering column illustrating a fifthexample according to an embodiment of the present invention.

FIG. 42 is a cross-sectional view of an outer column.

FIG. 43 is a cross-sectional view of the outer column and an upperbracket.

FIG. 44 is a conceptual diagram showing correlations between leveroperating force and holding force, part (A) illustrates a state in whicha restriction surface is provided on an outer column, and part (B)illustrates a state in which no restriction surface is provided on theouter column.

FIG. 45 is a schematic perspective view illustrating one example of asteering device mounted in a vehicle.

FIG. 46 is a schematic side view illustrating one example of a steeringdevice with a conventional structure.

FIG. 47 is a cross-sectional view taken along line J-J of FIG. 46.

FIG. 48 is a cross-sectional view of a portion for describing a problemof a steering device with a conventional structure.

DESCRIPTION OF EMBODIMENTS First Example of Embodiment

A first example according to an embodiment of the present invention willbe described with reference to FIGS. 1 to 25. A steering device in thisexample includes a steering wheel 1, a steering shaft 2 a, a steeringcolumn 4 a, a tightening mechanism 80, a steering force auxiliary device(an assist device and an electric power type steering device) 5 a, and asteering gear unit 7.

The steering shaft 2 a includes an inner shaft 8 a disposed relativelyforward and an outer shaft 9 a disposed relatively rearward. Here, a“forward and rearward direction” is assumed to correspond to a forwardand rearward direction of a vehicle body in which the steering device isinstalled.

The steering column 4 a is supported in a vehicle body 15 a. Forexample, the steering column 4 a has a cylindrical shape. Alternatively,the steering column 4 a can have a shape other than the cylindricalshape. The steering column 4 a includes at least a part of the steeringshaft 2 a. The steering shaft 2 a is inserted through the steeringcolumn 4 a. The steering shaft 2 a is rotatably supported on an innerdiameter side of the steering column 4 a via a plurality of rollingbearings (not shown). A part of the steering shaft 2 a is arranged toprotrude closer to a rear side than a rear end opening of the steeringcolumn 4 a. The steering wheel 1 is fixed to a rear end section of thesteering shaft 2 a.

An electric motor 32 a (the assist device 5 a) serving as a power sourceconfigured to exert an assisting force is disposed near a front endsection of the steering column 4 a. The electric motor 32 a is supportedon a gear housing 12 a fixed to the front end section of the steeringcolumn 4 a. A part of the inner shaft 8 a is inserted into the gearhousing 12 a. A front end section of the inner shaft 8 a is coupled to apredetermined shaft in the steering force auxiliary device 5 a. Forexample, a shaft joined to the predetermined shaft via a torsion bar orthe like in the steering force auxiliary device 5 a protrudes from afront end surface of a gear housing 12. Output torque (the assistingforce) of the electric motor 32 a is exerted on the steering shaft 2 athrough a speed reducer provided in the gear housing 12 a. The gearhousing 12 a is supported by and fixed to the vehicle body 15 a througha lower bracket 14 a.

In this example, the steering device includes both a tilt mechanism (anexample of a position adjusting mechanism) configured to adjust avertical position of the steering wheel 1 in accordance with a physiqueand a driving posture of a driver and a telescopic mechanism (an exampleof the position adjusting mechanism) configured to adjust a front andrear position of the steering wheel 1. Alternatively, the steeringdevice can include one of the tilt mechanism and the telescopicmechanism without including the other mechanism.

With regard to the telescopic mechanism, the inner shaft 8 a and anouter shaft 9 a are set to be able to transmit a turning force and to bedisplaceable with respect to one another in an axial direction. Forexample, the steering shaft 2 a has a spline engagement structure. Theinner shaft 8 a and the outer shaft 9 a are displaced (the steeringshaft 2 a is extended and contracted) in the axial direction so that afront and rear position of the steering wheel 1 can be adjusted.Furthermore, a total length of the steering shaft 2 a can be reduced dueto the above-described relative displacement even when a strong impactis received. The steering column 4 a includes an inner column 10 adisposed relatively forward and an outer column 11 a disposed relativelyrearward. The inner column 10 a is partially inserted into the outercolumn 11 a and is arranged to be movable relative to the outer column11 a in the axial direction. The inner column 10 a is partially enclosedby the outer column 9 a. A relative position of the inner column 10 aand the outer column 11 a in the axial direction (an insertion length ofthe inner column 10 a with respect to the outer column 11 a) varies sothat a total length of the steering column 4 a varies. In other words, afront end section of the outer column 11 a, which is disposed at arelatively rear side of the steering column 4 a, is loosely set withrespect to a rear end section of the inner column 10 a, which isdisposed at a relatively front side of the steering column 4 a, so thata relative displacement therebetween can be applied in the axialdirection. Thus, the total length of the steering column 4 a can beextended and contracted. The steering column 4 a is installable on thevehicle body 15 a with an upper bracket (a support bracket) 17 a. Theouter column 11 a is supported with respect to the upper bracket 17 a tobe able to be moved in the forward and rearward direction. The supportbracket 17 a is supported on the vehicle body 15 a through a lockingcapsule 18 a to be able to be detached (drop out) when receiving astrong impact. Here, the “axial direction” is assumed to correspond toan axial direction of the steering shaft 2 a or the axial direction ofthe outer column 11 a when there is no special mention.

With regard to the tilt mechanism, one end of the inner column 10 a issupported on the vehicle body 15 a by the lower bracket 14 a through thegear housing 12 a. The lower bracket 14 a supports the gear housing 12 ato be able to freely rock about a tilt shaft 16 a disposed in a widthdirection (to be substantially parallel to the width direction). Thesteering column 4 a is supported on the vehicle body 15 a in a mannerdisplaceable by rocking using the tilt shaft 16 a installed in the widthdirection as a center. The outer column 11 a is supported on the upperbracket 17 a to be movable in a vertical direction. Here, the “widthdirection” is assumed to correspond to a width direction of the vehiclebody in which the steering device is installed when there is no specialmention. Furthermore, the “vertical direction” is assumed to correspondto a vertical direction of the vehicle body in which the steering deviceis installed.

A basic constitution of the steering device in this example is asdescribed above. Next, a constitution of the outer column 11 a andperipheral parts thereof will be described in detail.

In this example, the outer column 11 a is configured by coupling a framebody (a main body part and a sandwiched portion main body) 34 made of alight alloy, such as an aluminum-based alloy and a magnesium-basedalloy, and a cylindrical body (a cylindrical member) 35 made of aniron-based alloy such as a carbon steel plate in the axial direction.Alternatively, the outer column 11 a is made of a light alloy such as analuminum-based alloy and a magnesium-based alloy, and can be configuredsuch that the frame body (the main body part and the sandwiched portionmain body) 34 disposed at a first half thereof and the cylindrical body(the cylindrical member) 35 disposed at a second half thereof arearranged in the axial direction and integrally coupled to each other.Alternatively and/or additionally, the outer column 11 a can have othermaterials and/or other constitutions. The frame body 34 is movablysupported on the upper bracket 17 a in the forward and rearwarddirection and the vertical direction. An axial slit 36 (a first slit)extending in the axial direction is formed in a lower surface of theframe body 34. A front end section of the axial slit 36 is open in afront end surface of the frame body 34. In addition, circumferentialslits 37 a and 37 b extending in a circumferential direction are formedin a portion near a front end of the frame body 34 and a portion near arear end thereof in a lower half thereof. The circumferential slit 37 aat a front side of the frame body 34 is formed to intersect a portionnear a front end of the axial slit 36 in the circumferential direction.The circumferential slit 37 b at a rear side of the frame body 34 isformed to intersect a portion near a rear end of the axial slit 36 inthe circumferential direction. Clamp parts 38 and 38 are formed toenclose both sides of the frame body 34 in the width direction using theaxial slit 36, the circumferential slit 37 a, and the circumferentialslit 37 b in three directions.

In the clamp parts 38 and 38, three sides are open to be continuous withthe axial slit 36 and the circumferential slits 37 a and 37 b, and theremaining one side is joined to the frame body 34. That is to say, withrespect to the clamp part 38, a non-fixed end is continuously formed atleast on two lateral sides, which are arranged to be spaced apart fromeach other in the axial direction, and on one side in a first directionintersecting the axial direction (a first intersecting direction; asubstantially vertical direction in this example). Furthermore, theother side of the clamp part 38 in the first direction is a fixed end.In other words, the clamp part 38 has a cantilever structure with thefixed end extending in the axial direction. The clamp part 38 is lowerin rigidity in at least the width direction than other portions of theframe body 34 and is elastically deformable in the width direction (aninner diameter thereof is elastically expandable and contractable). Forexample, each of the clamp parts 38 and 38 has an inner circumferentialsurface with a partial cylindrical surface shape. The clamp parts 38 and38 are provided adjacent to both sides of the axial slit 36 in thecircumferential direction. The clamp parts 38 and 38 have a shape inwhich the clamp parts extend in the axial direction and thecircumferential direction (or the first direction). Plate-likeprojecting plates (projecting parts) 39 and 39 are provided onintermediate portions in the first direction (the substantially verticaldirection in this example) of outer surfaces of the clamp parts 38 and38 in the width direction in a state in which the projecting platesprotrude outwardly in the width direction. Acting surfaces (thirdsurfaces, third acting surfaces, and pressed surfaces) 40 and 40receiving a tightening force of the tightening mechanism 80 are formedon lower end sections (portions lower than the projecting plates 39 and39) of the outer surfaces of the clamp parts 38 and 38 in the widthdirection. For example, the acting surface 40 has a flat surface shape.Additionally and/or alternatively, the acting surface 40 can have ashape other than a flat shape. Note that, in this example, the firstdirection intersects the width direction of the vehicle body and isorthogonal to the axial direction. Alternatively, the first directioncan substantially correspond to the circumferential direction of theouter column 11 a. Alternatively, the first direction can intersect theaxial direction in a different direction from the direction orthogonalto the axial direction. A second direction is assumed to be a directionintersecting the axial direction and the first direction. A substantialtightening direction of the tightening mechanism 80 may coincide withthe second direction. In this example, the second directionsubstantially coincides with the width direction of the vehicle body.Alternatively and/or additionally, the second direction can includedirections other than the width direction of the vehicle body.

The outer column 11 a includes a reinforcing bridge part (a reinforcingpart, a reinforcing structure, and a reinforcing member) 41 bridgedbetween both sides of the outer column 11 a in the second direction(substantially in the width direction of the vehicle body in thisexample). The reinforcing bridge part 41 is provided to extend to besubstantially continuous between both sides of the outer column 11 a inthe second direction, and to physically join both sides of the outercolumn 11 a in the second direction. In this example, the reinforcingbridge part 41 is provided on a lower portion of the frame body 34 tocover the clamp parts 38 and 38 from below. The reinforcing bridge part41 is integrally formed with the outer column 11 a. The reinforcingbridge part 41 includes a reinforcing plate 42 and a pair of joiningparts 43 a and 43 b. A shape of the reinforcing bridge part 41 viewedfrom the width direction is a substantially U shape (an angulated Ushape). The reinforcing plate 42 is disposed below the clamp parts 38and 38 and is provided to extend in the width direction and the forwardand rearward direction. The reinforcing plate 42 includes a flat plate(a central flat plate) 44 disposed at a center of the reinforcing platein the width direction and outer flat plates (lower extension parts) 45and 45 disposed on both sides of the reinforcing plate in the widthdirection and below the flat plate 44. The flat plate 44 and the outerflat plate 45 are provided to be continuous through a step part 46. Thereinforcing bridge part 41 has a crank-shaped cross section.

In this example, the joining part 43 a disposed relatively forward isprovided to extend upward from portions (the outer flat plates 45 and45) on both sides of a front end section of the reinforcing plate 42 inthe width direction. The joining part 43 a is joined to portions of alower surface of a front end section of the frame body 34 which areadjacent to a front side of the circumferential slit 37 a and are onboth sides which surround the axial slit 36 in the circumferentialdirection. The joining part 43 b disposed at the rear side of thereinforcing bridge part 41 is provided to extend upward from a rear endsection of the reinforcing plate 42. The joining part 43 b is joined toa portion of a lower surface of a rear end section of the frame body 34which is adjacent to a rear side of a rear end section of the axial slit36. Alternatively and/or additionally, the reinforcing bridge part 41can have a different constitution from the above.

In this example, the outer column 11 a includes the above-describedreinforcing bridge part 41 to have high twisting rigidity. Gaps (slits)47 and 47 with a substantially U shape (a substantially angulated Ushape) when viewed from the width direction (the second direction) areprovided between the reinforcing bridge part 41 and the clamp parts 38and 38. The gaps 47 and 47 have at least telescopic adjustment slots(first through holes, axial slits, and first slits) 21 a and 21 aextending in the axial direction (the axial direction of the outercolumn 11 a and the axial direction of the steering shaft 2 a) and thecircumferential slits (second slits) 37 a and 37 b provided to becontinuous in the slots 21 a and 21 a and extending in a direction whichintersects the slots 21 a and 21 a. The clamp parts 38 and 38 areprovided adjacent to the slots 21 a and 21 a. The slots 21 a and 21 aform spaces which are present between distal end sections (lower endsections) of the clamp parts 38 and 38 and upper surfaces of portions onboth sides of the flat plate 44 in the reinforcing plate 42 in the widthdirection. An adjusting rod 24 a is inserted through the slots 21 a and21 a in the width direction (the second direction).

Roller travel depressed grooves 48 and 48 are provided in portions onboth sides of the outer column 11 a in the width direction in the axialdirection of the slots 21 a and 21 a. The grooves 48 and 48 are providedin outer portions of the slots 21 a and 21 a in the width direction. Thegrooves 48 and 48 are enclosed in three directions by lower surfaces ofthe projecting plates 39 and 39 provided on the clamp parts 38 and 38,upper surfaces of the outer flat plates 45 and 45 of the reinforcingplate 42, outer surfaces (the acting surfaces 40 and 40) of distal endsections of the clamp parts 38 and 38 in the width direction, and outersurfaces of the step parts 46 and 46 of the reinforcing plate 42 in thewidth direction. In other words, the grooves 48 and 48 include the lowersurfaces of the projecting plates 39 and 39 as first lateral wallsurfaces, the upper surfaces of the outer flat plates 45 and 45 assecond lateral wall surfaces, the acting surfaces 40 and 40 of the clampparts 38 and 38 as first bottom surfaces, and the outer surfaces of thestep parts 46 and 46 as second bottom surfaces.

The outer column 11 a has an acting surface (a first surface, a firstacting surface, a first abutting surface, and a torque transmissionsurface) 49 a and an acting surface (a second surface, a second actingsurface, a second abutting surface, and a torque transmission surface)49 b which are provided on two lateral surfaces in the width direction.The acting surface 49 a and the acting surface 49 b are arranged to bespaced apart from each other in the first direction (the firstintersecting direction) serving as a direction which intersects theaxial direction (the axial direction of the outer column 11 a and theaxial direction of the steering shaft 2 a). Furthermore, the clamp part38 (and the acting surface 40) is arranged between the acting surface 49a and the acting surface 49 b in the first direction. In this example,the adjusting rod 24 a is arranged between the acting surface 49 a andthe acting surface 49 b in the first direction, and the acting surface40 of the clamp part 38 is arranged between the acting surface 49 a andthe adjusting rod 24 a in the first direction. Furthermore, the axialslit 36 (the slot 21 a) is arranged between the acting surface 49 a andthe acting surface 49 b in the first direction. In this example, torque(a force in a twist direction) acting on the outer column 11 a may betransmitted to inner surfaces of support plates 22 a and 22 a in theupper bracket 17 a via the acting surface 49 a and the acting surface 49b.

In this example, the acting surface 49 a is arranged within a range ofan external form of the inner column 10 a in the first direction. Theacting surface 49 b is arranged outside of the range of the externalform of the inner column 10 a in the first direction. In addition, theacting surface 49 b is arranged outside of a range of an external formof the cylindrical body 35 of the outer column 11 a. Furthermore, theacting surface 49 a is arranged relatively closer to a central axis ofthe inner column 10 a in the first direction, and the acting surface 49b is arranged relatively far from the central axis of the inner column10 a. Ridge parts 50 and 50 are provided on a portion near a centralaxis of the outer column 11 a in the first direction (or the verticaldirection) on both sides of the outer column 11 a (the frame body 34) inthe width direction to protrude outwardly in the width direction (thesecond direction). The ridge part 50 is provided to extend in the axialdirection of the outer column 11 a. The acting surfaces 49 a and 49 aare provided on distal ends of the ridge parts 50 and 50 (outer surfacesthereof in the width direction). In this example, depressed portions 51a and 51 b which are depressed in the width direction are provided inportions (front sections and rear sections) on both sides of the ridgeparts 50 and 50 in the forward and rearward direction. The actingsurfaces 49 a and 49 a have a shape in which two linear portionsextending in the axial direction are joined to the front and rear endsections on both sides of the ridge parts 50 and intermediate portionsthereof. On the other hand, the acting surface 49 b on a lower side ofthe outer column 11 a is provided on a distal end of the reinforcingplate 42 (the outer flat plates 45 and 45) (a lateral surface thereof inthe width direction). Both of the acting surfaces 49 a and 49 b have ashape in which the acting surfaces 49 a and 49 b extend in the axialdirection of the outer column 11 a, and the acting surfaces 49 a and 49b have a length longer in the axial direction than that of the clamppart 38. For example, the acting surface 49 a and the acting surface 49b have flat surface shapes. Additionally and/or alternatively, theacting surface 49 a and the acting surface 49 b can have shapes otherthan flat shapes. The acting surfaces 49 a and 49 b have rigidity higherin the width direction (the second direction) than those of the clampparts 38 and 38.

Upper end sections of the joining parts 43 a and 43 b in the reinforcingbridge part 41 are joined to be continuous to both end sections of theridge parts 50 and 50 in the forward and rearward direction. Both endsections of the acting surfaces 49 a and 49 b in the forward andrearward direction are joined to each other to be continuous usingcontinuous surfaces (for example, flat continuous surfaces) 52 a and 52b formed on lateral surfaces of the joining parts 43 a and 43 b in thewidth direction to extend in the vertical direction. The acting surfaces49 a and 49 b and the continuous surfaces 52 a and 52 b are formed insubstantially rectangular frame shapes. In this example, the actingsurfaces 49 a and 49 b and the continuous surfaces 52 a and 52 b arelocated on the same virtual plane and are located slightly closer toouter sides of the projecting plates 39 and 39 in the width directionthan end surfaces of the projecting plates 39 and 39 in the widthdirection.

A locking depressed groove 53 extending in the circumferential directionis formed in an inner circumferential surface of a front end section ofthe outer column 11 a (the frame body 34). For example, a slide member54, which is made of a synthetic resin with excellent slidability suchas a polyamide resin, a polyacetal resin, and a polytetrafluoroethyleneresin and having a whole shape in a substantially C shape, is attachedin the locking groove 53 and the axial slit 36. Alternatively and/oradditionally, the slide member 54 can include other materials and/orother constitutions. The slide member 54 includes a slide part main body55 and a pair of support arms 56 and 56 with a partial circular arcshape extending from both sides of the slide part main body 55 in thewidth direction. The slide part main body 55 is disposed in the axialslit 36. The support arms 56 and 56 are disposed in the locking groove53. In a state in which the slide member 54 is mounted, an upper surfaceof the slide part main body 55 and an inner circumferential surface ofthe frame body 34 are located on the same imaginary cylindrical surfaceor slightly protrudes inward therefrom in a radial direction. A pair ofdepressed portions 57 and 57, which are depressed in the axialdirection, are formed in the slide part main body 55. The two depressedportions 57 and 57 are arranged adjacent to each other in the widthdirection (the circumferential direction). The slide part main body 55is set to have relatively low rigidity in the vertical direction.

Note that, in this example, particularly with regard to a basicconstitution of the outer column 11 a, a brief description from anotherviewpoint will be provided. A pair of sandwiched plates are integrallyformed with the outer column 11 a in a state in which the axial slit 36is sandwiched from both sides thereof in the width direction by thesandwiched plates, and distal end sections (lower end sections) of thesandwiched plates are joined to the outer column 11 a in the widthdirection in this example (by a portion corresponding to the reinforcingplate 42). Moreover, outer surfaces of the sandwiched plates in thewidth direction are set as tightening surfaces with a substantially flatsurface shape. The gaps (the slits) 47 and 47 with the substantially Ushape and which communicate with an inner circumferential surface of theouter column 11 a are formed in substantially central positions of thetightening surfaces, and portions enclosed by the gaps 47 and 47 are setas the clamp parts 38 and 38. Moreover, upper sides and lower sides ofthe tightening surfaces are set as the acting surfaces 49 a and 49 b.

As shown in FIG. 1 and FIG. 2, the upper bracket (the support bracket)17 a is made of, for example, a metal plate of steel, an aluminum-basedalloy, or the like with sufficient rigidity. The upper bracket 17 aincludes an attachment plate 58 and the pair of the support plates 22 aand 22 a. For example, the attachment plate 58 has an L-shaped crosssection. Alternatively and/or additionally, the attachment plate 58 canhave other materials and/or other shapes. The attachment plate 58 isnormally supported on the vehicle body 15 a. The attachment plate 58 isconfigured such that the attachment plate 58 is detached forward and aforward displacement of the outer column 11 a is allowed on the basis ofan impact such as a secondary collision. A pair of locking cutouts 59and 59 are formed in a rear edge of the attachment plate 58 in an openstate. The locking capsules 18 a and 18 a fixed to the vehicle body 15 ausing fixing members such as bolts or studs are locked into the lockingcutouts 59 and 59. Locking grooves 60 and 60 configured to be engagedwith right and left edge portions of the locking cutouts 59 and 59 areformed in right and left lateral surfaces of the locking capsules 18 aand 18 a, and through holes 61 and 61 through which both of the fixingmembers are inserted are formed in central portions of the lockingcapsules 18 a and 18 a.

The support plates 22 a and 22 a are provided to hang from an attachmentplate 55. Furthermore, the support plates 22 a and 22 a are provided tobe parallel to each other in a state in which the front end section (theframe body 34 and the reinforcing bridge part 41) of the outer column 11a is sandwiched from both sides thereof in the width direction by thesupport plates 22 a and 22 a. The pair of support plates 22 a and 22 aare arranged on both of the sides of the outer column 11 a in the widthdirection (the second direction). Tilt adjustment slots (second throughholes) 23 a and 23 a extending in at least the vertical direction (thefirst direction) are formed in the support plates 22 a and 22 a. Theslots 23 a and 23 a are provided in opposing positions (positionsmatching each other) in the width direction. Furthermore, the slots 23 aand 23 a are provided to match a portion of telescopic adjustment slots21 a and 21 a in the forward and rearward direction. The slots 23 a and23 a have long axes in the vertical direction (the first direction). Thesupport plates 22 a and 22 a are arranged to be able to tighten theouter column 11 a (the steering column 4 a) using the tighteningmechanism 80. The tightening mechanism 80 includes the adjusting rod 24a, an adjusting nut 25, an adjusting lever 26 a, and the like. Theadjusting rod 24 a is inserted through the telescopic adjustment slots21 a and 21 a and the tilt adjustment slots 23 a and 23 a in the widthdirection.

The adjusting rod 24 a includes an anchor part 27 a disposed on one endsection, a male screw part formed in the other end section, and a shaftpart 62 formed on an intermediate portion in the width direction (theaxial direction and the second direction of the adjusting rod 24 a). Inthis example, a pair of rollers 63 and 63 are rotatably supported on theshaft part 62 in a state in which the rollers are spaced apart from eachother in the width direction. The rollers 63 and 63 are constituted of,for example, roller bodies 64 and 64 made of a metal and collars 65 and65 manufactured by an elastic material made of a synthetic resin such asa polyamide resin (nylon) and a polytetrafluoroethylene (PTFE) resin orrubber. Alternatively and/or additionally, the rollers 63 and 63 caninclude other materials and/or other constitutions. The roller bodies 64and 64 have a substantially cylindrical shape, as shown in FIGS. 18 to20. Through holes 66 and 66 through which the shaft part 62 is insertedare formed in central portions of the roller bodies 64 and 64. Flanges67 and 67 with an outward flange shape are formed on end sections ofouter circumferential surfaces of the roller bodies 64 and 64 in thewidth direction. Thin parts 68 and 68 with a circular arc cross section,which are depressed in the width direction, are formed on intermediateportions of the roller bodies 64 and 64 in a radial direction at aplurality of (four in the illustrated example) locations at equalcircumferential intervals in the circumferential direction. The collars65 and 65 have a cylindrical shape as shown in FIGS. 21 to 23. Athickness dimension of the collars 65 and 65 is larger than a heightdimension of the flanges 67 and 67 in a radial direction. In the rollers63 and 63 in this example, the collars 65 and 65 are press-fitted to(externally engaged with) portions of the outer circumferential surfacesof the roller bodies 64 and 64 which are deviated from the flanges 67and 67 in the width direction. Alternatively, one long/elongated rollerwhich is continuously elongated in the width direction can also be usedin the width direction instead of a pair of rollers, or the whole rollercan be made of a synthetic resin or rubber.

Outer end surfaces of the rollers 63 and 63 in the width direction arelocated slightly closer to an outer side in the width direction than endsurfaces of the projecting plates 39 and 39 in the width direction in astate in which the adjusting rod 24 a is inserted through the telescopicadjustment slots 21 a and 21 a and the tilt adjustment slots 23 a and 23a, and the rollers 63 and 63 are disposed in the roller travel grooves48 and 48.

The anchor part 27 a is provided on one end side of the adjusting rod 24a in the width direction. The anchor part 27 a is relativelynon-rotatably engaged with the tilt adjustment slot 23 a formed in oneof the support plates 22 a. A cam device 69, which is constituted of adriving-side cam and a driven-side cam, and the adjusting lever 26 a areprovided in the vicinity of a portion of the adjusting rod 24 a (theshaft part 62) which protrudes in the width direction from an outersurface of the other support plate 22 a in the width direction. A nut 70is screwed on the male screw part. The driving-side cam of the camdevice 69 is rotated relative to the driven-side cam on the basis of arocking operation of the adjusting lever 26 a in the tighteningmechanism 80 so that a width dimension (a dimension of the adjusting rod24 a in the axial direction) of the cam device 69 is expandable andcontractable.

In this example, a tilt spring (a tilt flip-up spring or a balancespring) 72A serving as a coil spring is provided in the attachment plate58 in the upper bracket 17 a. The tilt spring 72A is bridged between abent part 71A provided on a front end section in the attachment plate 58and the cam device 69 (the driven-side cam). An upward biasing force isexerted on the adjusting rod 24 a via the cam device 69 using the tiltspring 72A. The biasing force exerted on the adjusting rod 24 a istransmitted to the lower surfaces of the projecting plates 39 and 39constituting upper sides of the roller travel grooves 48 and 48 via therollers 63 and 63, and thus the outer column 11 a is pressed upward.

In this example, the steering device includes a steering lock deviceserving as a type of a vehicle anti-theft device. A locking through hole33 a is formed to pass through a portion of the outer column 11 a near afront end of the cylindrical body 35 in a radial direction. As shown inFIG. 10, a lock unit 73 is supported by and fixed to the vicinity of thelocking through hole 33 a, and a key lock collar 74 is externally-fitted(press-fitted) to the steering shaft 2 a. The key lock collar 74 isarranged at a portion at which phases of the key lock collar 74 and thelock unit 73 coincide with each other at a part of the steering shaft 2a in the axial direction. When an ignition key is switched off in thelock unit 73, a distal end section of a lock pin 75 is displaced towardan inner diameter of the outer column 11 a and is engaged with a keylock depressed portion 76 formed in an outer circumferential surface ofthe key lock collar 74. Thus, the steering shaft 2 a cannot besubstantially rotated. That is to say, the key lock depressed portion 76is engaged with the distal end section of the lock pin 75 in a state inwhich the steering shaft 2 a cannot be substantially rotated at a timeof key locking. A predetermined value (for example, a value defined bykey lock regulations; a limit value) used to release a non-rotatablestate is set for the lock unit 73. Rotation of the steering shaft 2 a bya force with an extent that the steering wheel 1 (refer to FIG. 45) isoperated by a normal driving posture as it is prevented. When thesteering wheel 1 (refer to FIG. 45) is rotated using a force greaterthan or equal to the predetermined value, the steering shaft 2 a can berotated with respect to the key lock collar 74 and the steering column 4a.

In this example with the above-described constitution, the tighteningmechanism 80 has a first state (a first form and a first mode) in whichthe outer column 11 a (the steering column 4 a) is tightened through anupper bracket (a support bracket) 17 a, and a second state (a secondform and a second mode) in which the tightening is released.

When the steering wheel 1 is moved to a desired position and is thenheld at a desired position, the adjusting lever 26 a of the tighteningmechanism 80 is rocked (turned) about the adjusting rod 24 a in apredetermined direction (generally, upward). As a result, a widthdimension of the cam device 69 increases, and an interval between theinner surfaces of the support plates 22 a and 22 a decreases. Therollers 63 and 63 are pressed inward in the width direction by the innersurfaces of the support plates 22 a and 22 a. The acting surfaces 40 and40 (bottom surfaces of the roller travel grooves 48 and 48) formed onthe lower end sections (the distal end sections) of the clamp parts 38and 38 are pressed by inner surfaces of the rollers 63 and 63 in thewidth direction. The clamp parts 38 and 38 are bent (elasticallydeformed) inwardly in the width direction (toward an axial center), andan outer circumferential surface of the inner column 10 a is elasticallysandwiched (held) using the clamps 38 and 38 (is tightened in thetightening direction (the second direction)). Thus, the steering wheel 1is held in the adjusted position. Furthermore, when the clamp parts 38and 38 are bent to some extent, the acting surfaces 49 a and 49 b (andthe flat continuous surfaces 52 a and 52 b) are pressed inwardly in thewidth direction by the inner surfaces of the support plates 22 a and 22a. That is to say, in the first state, the outer column 11 a issandwiched from both sides of the outer column 11 a in the widthdirection by the inner surfaces of the support plates 22 a and 22 athrough the acting surfaces 49 a and 49 b (is tightened in thetightening direction (the second direction)).

On the other hand, when a position of the steering wheel 1 is adjusted,the adjusting lever 26 a is rocked (turned) in an opposite direction(generally, downward) to the predetermined direction. As a result, thewidth dimension of the cam device 69 decreases and the interval betweenthe inner surfaces of both of the support plates 22 a and 22 aincreases. Since a pressing force on the rollers 63 and 63 by thesupport plates 22 a and 22 a decreases, a width dimension between theclamp parts 38 and 38 elastically increases and a holding force of theouter circumferential surface of the inner column 10 a decreases (thetightening is released). In the second state, the front and rearposition and the vertical position of the steering wheel 1 can beadjusted in a range in which the adjusting rod 24 a can be moved withinthe telescopic adjustment slots 21 a and 21 a and the tilt adjustmentslots 23 a and 23 a.

In the steering device of this example, the acting surfaces 49 a and 49a, the acting surfaces 49 b and 49 b, and the acting surfaces 40 and 40of the clamp parts 38 and 38 are provided on both of the sides of theouter column 11 a in the width direction (the second direction and thetightening direction). The acting surfaces 49 a and 49 a and the actingsurfaces 49 b and 49 b are directly pressed onto the support plates 22 aand 22 a of the upper bracket 17 a in the tightened state (the firststate). The acting surfaces 40 and 40 of the clamp parts 38 and 38 areindirectly pressed onto the support plates 22 a and 22 a through therollers 63 and 63 in the tightened state (the first state). The actingsurface (the first surface) 49 a, the acting surface (the secondsurface) 49 b, and the acting surface (the third surface) 40 aresubstantially independent of each other. The acting surfaces 49 a and 49a and the acting surfaces 49 b and 49 b are provided on the frame body34 of the outer column 11 a, and positions thereof with respect to theinner column 10 a do not substantially change, or amounts ofdisplacement thereof are slight while transitioning from the releasedstate (the second state) to the tightened state (the first state). Aposition of the acting surface 40 of the clamp part 38 with respect tothe inner column 10 a changes with a relatively large amount ofdisplacement (is displaced toward the inner column 10 a) (a displacementsurface) while transitioning from the released state (the second state)to the tightened state (the first state). In the first state, the outercolumn 11 a and the support plates 22 a and 22 a are coupled to eachother by a force acting on the acting surfaces 49 a and 49 a mainly at aposition near the central axis of the outer column 11 a. In the firststate, the outer column 11 a and the support plates 22 a and 22 b arecoupled to each other by a force acting on the acting surfaces 49 b and49 b mainly at a position away from the central axis of the outer column11 a. In the first state, the inner column 10 a is held mainly in theouter column 11 a through the clamp part 38 by a force acting on theacting surfaces 40 and 40. Therefore, in the steering device in thisexample, securing strength of the outer column 11 a and securing aholding force of the inner column 10 a are simultaneously andindependently realized, and a position adjusting mechanism with highstability is provided.

FIG. 46 and FIG. 47 illustrate the conventional steering devicedisclosed in Patent Literature 1. In the conventional steering device, afront and rear position and a vertical position of a steering wheel 1needs to be able to be adjusted, and an outer column 11 is movablysupported on an upper bracket 17 in a forward and rearward direction anda vertical direction. A slit 19 extending in an axial direction of theouter column 11 is formed in a lower surface of a front end section ofthe outer column 11. A pair of clamp parts 20 and 20 are integrallyformed with the outer column 11 in a state in which the slit 19 issandwiched from both sides thereof in a width direction by the clampparts 20 and 20. Moreover, telescopic adjustment slots 21 and 21, whichare elongated in the forward and rearward direction, are formed atpositions in which the clamp parts 20 and 20 are mutually matched. Inaddition, a pair of support plates 22 and 22 are provided in the upperbracket 17 in a state in which the clamp parts 20 and 20 are sandwichedfrom both sides thereof in the width direction by support plates 22 and22. Tilt adjustment slots 23 and 23, which are elongated in the verticaldirection, are formed in portions at which the support plates 22 and 22partially match and which partially match the telescopic adjustmentslots 21 and 21 in the forward and rearward direction. An adjusting rod24 is inserted through the telescopic adjustment slots 21 and 21 and thetilt adjustment slots 23 and 23 in the width direction (the right to theleft of FIG. 47) in a state in which the clamp parts 20 and 20 aresandwiched by the support plates 22 and 22 of the upper bracket 17. Theadjusting nut 25 is screwed on another end of the adjusting rod 24. Theadjusting nut 25 can be rotated through an adjusting lever 26.

In the conventional steering device, the adjusting nut 25 is rotated onthe basis of an operation of the adjusting lever 26. The outer column 11is fixed to the upper bracket 17 or the fixing is released along with achange in an interval between the adjusting nut 25, the anchor part 27,and the adjusting rod 24. In addition, the outer column 11 is fixed toan inner column 10 or the fixing is released along with an intervalbetween the clamp parts 20 and 20. The adjusting rod 24 can be displacedinside the telescopic adjustment slots 21 and 21 in the forward andrearward direction in a state in which an interval between the adjustingnut 25 and the anchor part 27 increases. The outer column 11 is movedforward and rearward (is displaced relative to the inner column 10) insuch a displaceable range (a telescopic adjustment range) so that thefront and rear position of the steering wheel 1 can be adjusted. Inaddition, the adjusting rod 24 can be displaced inside the tiltadjustment slots 23 and 23 in a substantially vertical direction. Thevertical position of the steering wheel 1 can be adjusted in such adisplaceable range (a tilt adjustment range). At this time, a steeringcolumn 4 is rocked and displaced about a tilt shaft 16 in the verticaldirection.

A front end section of an output shaft 13 in a steering force auxiliarydevice 5 is joined to a rear end section of an intermediate shaft 29through a universal joint 28. An input shaft 31 of a steering gear unit7 is joined to a front end section of the intermediate shaft 29 throughanother universal joint 30. The steering gear unit 7 includes a rack anda pinion (which are not shown), and the input shaft 31 is coupled to thepinion. Both end sections of the rack meshed with the pinion are joinedto tie rods 6 and 6. The tie rods 6 and 6 are pushed and pulled on thebasis of a displacement of the rack in the axial direction so that adesired steering angle is given to a steering wheel 3 (refer to FIG.45). The steering force auxiliary device 5 can give auxiliary torque ata predetermined size in a predetermined direction to the output shaft 13through a worm speed reducer using an electric motor 32.

In the conventional steering device, when frictional forces betweeninner surfaces of the support plates 22 and 22 and outer surfaces of theclamp parts 20 and 20 decrease due to an operation in which a positionof the steering wheel 1 needs to be able to be adjusted and which isperformed through the adjusting lever 26, a rear end section of theouter column 11 is tilted downward in some cases. This is because adownward force acts on the rear end section of the outer column 11through an outer shaft 9 on the basis of a weight of the steering wheel1. A gap with a certain size is provided between an innercircumferential surface of the outer column 11 and an outercircumferential surface of the inner column 10 due to relativedisplacement in the axial direction between the inner column 10 and theouter column 11.

In this case, a contact state of a contact portion, which is in aportion X indicated by a circle in FIG. 48, of an upper end section of arear edge of the inner column 10 and an inner circumferential surface ofthe outer column 11 is a line contact. In addition, a contact state of acontact portion, which is in a portion Y indicated by a circle in FIG.48, of a lower end section of a front edge of the outer column 11 and anouter circumferential surface of the inner column 10 is a line contact.As a result, when the front and rear position of the steering wheel 1needs to be able to be adjusted and the outer column 11 is displacedrelative to the inner column 10, the outer column 11 is likely to catchthe inner column 10 (to twist). This phenomenon reduces an operationalfeeling of adjusting the front and rear position of the steering wheel 1and causes an operational load in the forward and rearward direction toincrease. Particularly, in the case of a column type electric powersteering device (a column type electric power steering (EPS) device) inwhich the steering force auxiliary device 5 is combined with a steeringcolumn 2 like in the illustrated structure, a fit length of the innercolumn 10 and the outer column 11 is set to be relatively short due torestrictions on an installation space of the steering column 4. As aresult, an angle of inclination of the outer column 11 easily increases,and thus the above-described problem easily occurs. A new problem occursin that processing costs increase due to precision machining such as atask of reducing a gap between an outer column and an inner column andchamfering performed on an outer circumferential edge of an end sectionof the inner column.

As shown in FIG. 10, in the steering device in this example, theadjusting rod 24 a is biased upward by the tilt spring 72A. Such abiasing force F1 is transmitted to the front end section (the frame body34) of the outer column 11 a via the rollers 63 and 63. The outer column11 a is pressed upward by the biasing force F1 even when a force F2 in adirection which presses the rear end section of the outer column 11 adownward is applied to a rear end section of the outer column 11 a onthe basis of the weight of the steering wheel 1. As a result, a slope ofthe outer column 11 a is zero or can be reduced (the rear end sectioncan be prevented from being tilted downward). In addition, a gap issecured between an upper end section of the inner circumferentialsurface of the outer column 11 a and an upper end section of the outercircumferential surface of the inner column 10 a. Therefore, an upperend section in a rear edge of the inner column 10 a comes more firmlyinto line contact with the inner circumferential surface of the outercolumn 11 a. For this reason, the occurrence of catching (twisting) whenthe front and rear position of the steering wheel 1 is adjusted can beeffectively prevented.

In addition, in the steering device in this example, the biasing forceexerted on the adjusting rod 24 a is transmitted to the outer column 11a (the lower surfaces of the projecting plates 39 and 39) via therollers 63 and 63. When the front and rear position of the steeringwheel 1 needs to be able to be adjusted and the outer column 11 a isdisplaced relative to the inner column 10 a in the forward and rearwarddirection, the rollers 63 and 63 travel (roll) along the lower surfacesof the projecting plates 39 and 39. Frictional resistance generated whenthe outer column 11 a is displaced relative to the inner column 10 a inthe forward and rearward direction is suppressed to be small compared towhen the outer column is directly biased by the adjusting rod. Notethat, in a constitution in which no roller is used, a sleeve or the likemade of a resin is used for a sliding contact portion between theadjusting rod and the outer column to secure slidability so that slidingresistance can be reduced. However, a surface pressure increases, and aproblem easily occurs in terms of durability because the outercircumferential surface of the adjusting rod comes into line contactwith the sleeve. On the other hand, in the steering device in thisexample, a rolling contact is used, and thus such a problem is avoided.Moreover, in the steering device in this example, the collars 65 and 65made of a synthetic resin are used as outer circumferential surfaces ofthe rollers 63 and 63, and thus sliding based on contact between metalsis avoided and the rollers 63 and 63 can be effectively rotated.Moreover, in the steering device in this example, since the biasingforce is exerted on the adjusting rod 24 a through the tilt spring 72A,the biasing force is exerted on a whole region of the steering wheel 1in a forward and rearward adjustment range. Here, the front and rearposition of the steering wheel 1 is smoothly adjusted in a state inwhich the rollers 63 and 63 are sandwiched so that the biasing force isexerted upward.

In addition, in the steering device in this example, since the slidepart main body 55 is provided on a lower end section of a front edge ofthe outer column 11 a (the frame body 34), an upper surface of the slidepart main body 55 is in contact with an outer circumferential surface ofthe inner column 11 a. As a result, a contact form of a lower endsection of a front edge of the outer column 11 a and the outercircumferential surface of the inner column 10 a is prevented frombecoming a line contact. Therefore, catching at such a portion issuppressed to be small, and thus sliding resistance can be preventedfrom being excessively increased at a time of front and rear positionadjustment.

The steering device in this example can be preferably applied even whenthe total length of the steering column 4 a is relatively short. That isto say, the catching (the twisting) at the time of adjusting the frontand rear position of the steering wheel 1 is prevented even when aconstitution of the column EPS has been adopted, and a high operationfeeling is obtained at the time of adjusting the front and rear positionof the steering wheel 1, and thus an operational load is suppressed tobe small low.

In the conventional steering device, for example, the anti-theftsteering lock device disclosed in Patent Literature 2 is incorporated insome cases. In this case, a problem is likely to occur in terms ofsecuring durability of the outer column 11. The steering lock device isconstituted by mounting the lock unit (a key lock cylinder) around alocking through hole 33 partially formed in the outer column 11 and thekey lock collar on a part of the steering shaft 2. In a state in whichthe ignition key is pulled out, a key lock pin provided in the lock unitis engaged with a key lock hole (a depressed portion) provided in thekey lock collar, and thus rotation of the steering shaft 2 with respectto the outer column 10 can be prevented.

When forcible rotation of the steering wheel 1 is attempted in a statein which such a steering lock device has been operated, torque (atwisting force) is sequentially transmitted to the steering shaft 2, thekey lock collar, the lock unit, the outer column 11, and the upperbracket 17, and the steering wheel 1 is ultimately supported on thevehicle body 15. Particularly, the torque transmitted from the lock unitis transmitted to the pair of support plates 22 and 22 between the outercolumn 11 and the upper bracket 17 via the clamp parts 20 and 20, onwhich a pressing force from the support plates 22 and 22 acts, in theouter column 11 which constitute the upper bracket 17. For this reason,strengths of base portions of the clamp parts 20 and 20 are likely to beinsufficient. When thicknesses of the base portions of the clamp parts20 and 20 are increased (reinforced) to solve such a problem, it isdifficult to bend the clamp parts 20 and 20, and thus a holding force ofthe inner column 10 is less likely to be sufficiently secured.

As shown in FIGS. 2, 3 and the like, in the steering device in thisexample, the acting surface 40 of the clamp part 38 and the actingsurfaces 49 a and 49 b are separately provided on both of the sides ofthe outer column 11 a in the width direction. The clamp parts 38 and 38are used for elastically sandwiching the outer circumferential surfaceof the inner column 10 a. On the other hand, for example, when thesteering wheel 1 has been operated by a large force while the steeringlock device and the like is being operated, the torque acting on theouter column 11 a is transmitted to the inner surfaces of the supportplates 22 a and 22 a of the upper bracket 17 a via the acting surfaces49 a and 49 b. The clamp parts 38 and 38 may be adopted as long as theclamp parts 38 and 38 can exhibit only a function of sandwiching theinner column 10 a. For this reason, it is not necessary to set anexcessively high strength to the clamp parts 38 and 38. Therefore, inthe steering device in this example, desired bending characteristicssuch as greatly bending the clamp parts 38 and 38 in the width directioncan be set for the clamp parts 38 and 38. On the other hand, the actingsurfaces 49 a and 49 b may be adopted as long as the acting surfaces 49a and 49 b can exhibit only a function of transmitting the torque. Forthis reason, it is not necessary to greatly bend sections in which theacting surfaces 49 a and 49 b in the outer column 11 a are installed inthe width direction. Therefore, according to the steering device in thisexample, securing the strength of the outer column 11 a can beindependently compatible with securing the holding force of the innercolumn 10 a.

Moreover, in the steering device in this example, the inner surfaces ofthe support plates 22 a and 22 a are brought into contact with (pressedby) the acting surfaces 49 a and 49 b to hold the steering wheel 1 atthe desired position. At this time, the clamp parts 38 and 38 are bentthrough the inner surfaces of the support plates 22 a and 22 a. In theouter column 11 a, the acting surfaces 49 a and 49 b are substantiallyindependent from the acting surface 40 of the clamp part 38, and theportions in which the acting surfaces 49 a and 49 b are installed havesufficiently high rigidity (bending rigidity and bent characteristics)compared to the clamp part 38. Furthermore, the acting surface 49 a andthe acting surface 49 b are arranged to be spaced apart from each otherin the first direction which intersects the second direction (thetightening direction). Particularly, a position of the acting surface 49b is outside of the range of the external form of the inner column 10 ain the first direction, and is outside of a range of the external formof the cylindrical body 35 of the outer column 11 a. For this reason,the torque acting on the outer column 11 a is absorbed through theacting surfaces 49 a and 49 b, and thus the torque can be prevented frombeing transmitted to the clamp part 38.

Second Example of Embodiment

A second example according to an embodiment of the present inventionwill be described with reference to FIG. 26 and FIG. 27. Particularly,shapes of clamp parts 38 a and 38 a configured to elastically surroundan outer circumferential surface of an inner column 10 a in a steeringdevice in this example are different from those of the above-describedfirst example according to an embodiment. In the following description,constituent parts which are the same as or equivalent to those of theabove-described will be denoted with the same reference numerals, and adescription thereof will be simplified or omitted.

In the steering device in this example, cross-sectional shapes of theclamp parts 38 a and 38 a associated with a virtual plane orthogonal toa central axis O₁₁ of an outer column 11 b have symmetrical shapes withrespect to a virtual line V passing through the central axis O₁₁ of theouter column 11 b and orthogonal to a central axis O₂₁ of slots (slits)21 b and 21 b between the clamp parts 38 a and 38 a. Moreover, thecross-sectional shapes of the clamp parts 38 a and 38 a are constant(has a symmetrical shape in a forward and rearward direction) over anentire length in an axial direction. The clamp part 38 a has asubstantially symmetrical shape and symmetrical structure with respectto a symmetry axis along a first direction that intersects the axialdirection. In this example, an acting surface 40 of the clamp part 38 ahas a substantially symmetrical shape with respect to the symmetry axis.In other words, a center of the acting surface 40 in the axial directionis located on the symmetry axis. In addition, in this example, centersof an acting surface 49 c and an acting surface 49 d of an outer column11 a in the axial direction coincide with a center of the clamp part 38a. For example, the centers of the acting surface 49 c and the actingsurface 49 d in the axial direction coincide with the center of theacting surface 40 of the clamp part 38 a. Furthermore, a center of atelescopic adjustment slot 21 a in the axial direction coincides withthe centers of the acting surface 49 c, the acting surface 49 d, and theacting surface 40.

In the steering device in this example, circumferential slits 37 c and37 d extending linearly in a circumferential direction are formed in aframe body 34 a of the outer column 11 b. The circumferential slits 37 cand 37 d are provided to intersect portions near front and rear ends ofan axial slit 36 formed in a lower surface of the frame body 34 a in thecircumferential direction. The clamp part 38 a enclosed in threedirections by the axial slit 36, the circumferential slit 37 c, and thecircumferential slit 37 d is formed on portions near both sides of theframe body 34 a in a width direction. In the steering device in thisexample, a gap 47 a (a slit) is formed between the clamp part 38 a and areinforcing bridge part 41. A shape of the gap 47 a viewed from thewidth direction is a substantially U shape (a substantially angulated Ushape) in which front and rear end sections thereof are bent at rightangles. Torque acting on the outer column 11 b is transmitted to innersurfaces of support plates 22 a and 22 a of an upper bracket 17 a (referto FIG. 2 and the like) through the acting surfaces 49 c and 49 d. Theacting surfaces 49 c and 49 d have a symmetrical shape in the forwardand rearward direction. The acting surfaces 49 c and 49 d and continuousflat surfaces 52 a and 52 b are continuous in rectangular (quadrangular)frame shapes.

In the steering device in this example with the above-describedconstitution, the clamp parts 38 a and 38 a are bent using the innersurfaces of the support plates 22 a and 22 a such that a steering wheel1 (refer to FIG. 46) is held at a desired position. At this time,concentration of stress on a part of the clamp parts 38 a and 38 a isprevented clamp part regardless of a front and rear position of anadjusting rod 24 a (refer to FIG. 2) in telescopic adjustment slots 21 band 21 b. For this reason, damage to the clamp parts 38 a and 38 a canbe prevented regardless of a load acting on the clamp parts 38 a and 38a (lower surfaces of projecting plates 39 and a pressed surface 40) invarious directions {a vertical direction, the width direction (ahorizontal direction of FIG. 27), and a direction of rotation (about thecentral axis O₁₁)} from rollers 63 and 63 disposed in the telescopicadjustment slots 21 b and 21 b. The clamp parts 38 a and 38 a are setsuch that amounts of bending thereof are the same so that holding forceof the inner column 10 a is stabilized. In the steering device in thisexample, the telescopic adjustment slots 21 b and 21 b can be designedsuch that a dimension thereof in the forward and rearward direction islarger than that of the case of the above-described first example. Inthis case, an adjustment length in the forward and rearward direction ofthe steering wheel 1 increases. Other constitutions and operationaleffects are the same as those of the case of the first example.

Third Example of Embodiment

A third example according to an embodiment of the present invention willbe described with reference to FIGS. 28 to 38. In the followingdescription, constituent parts which are the same as or equivalent tothose of the above-described will be denoted with the same referencenumerals, and a description thereof will be simplified or omitted.

Particularly, structures of clamp parts 38 a and 38 a in a steeringdevice in this example are different from those of the above-describedfirst example according to the embodiment. In this example, projectingplates (projecting parts) 39 and 39 are provided on lower end sectionsof outer surfaces of the clamp parts 38 and 38 in a width direction in astate in which the projecting plates (projecting parts) 39 and 39protrude outward in the width direction (a second direction). Actingsurfaces (a third surface, a third acting surface, and a pressedsurface) 40 and 40 are formed outside the projecting plates 39 and 39 inthe width direction (the second direction). For example, the actingsurface 40 has a flat surface shape. Additionally and/or alternatively,the acting surface 40 can have a shape other than a flat shape.Reinforcing ribs 51 and 51 are provided between upper surfaces (lateralsurfaces of walls) of the projecting plate 39 and 39 andcylindrical-surface-shaped upper end sections or intermediate portionsof outer surfaces of the clamp parts 38 and 38 in the width direction.On each side, the plurality of reinforcing ribs 51 (an example in whichfive reinforcing ribs 51 is in the drawing) are provided to extend inthe width direction and are disposed to be spaced apart from each otherin a forward and rearward direction (an axial direction).

An outer column 11 a includes a reinforcing bridge part (a reinforcingpart, a reinforcing structure, and a reinforcing member) 41 bridgedbetween both sides of the outer column 11 a in the width direction (thesecond direction). The reinforcing bridge part 41 is provided to extendto be substantially continuous between both of the sides of the outercolumn 11 a in the width direction (the second direction) and tophysically join both of the sides of the outer column 11 a in the widthdirection (the second direction). In this example, the reinforcingbridge part 41 is provided at a lower portion of a frame body 34 in astate in which the reinforcing bridge part 41 covers the clamp parts 38and 38 from below. The reinforcing bridge part 41 is integrally formedwith the outer column 11 a. The reinforcing bridge part 41 includes areinforcing plate 42 and a pair of joining parts 43 a and 43 b. A shapeof the reinforcing bridge part 41 viewed from the width direction issubstantially a U shape (an angulated U shape). The reinforcing plate 42is disposed below the clamp parts 38 and 38, and is provided to extendin the width direction and the forward and rearward direction. In thisexample, the reinforcing plate 42 includes a flat plate 44 disposedparallel to a central axis of the outer column 11 a and a pair ofdownward extending parts 45 and 45 provided to extend downward from alower surface of both end sections of the flat plate 44 in the widthdirection. For example, the reinforcing plate 42 has a substantiallyangulated U shaped cross section. Moreover, a cutout 46 passing in avertical direction is formed in an intermediate portion of a front endsection of the reinforcing plate 42 (the flat plate 44) in the widthdirection. Moreover, a plurality of (three in the illustrated example)flat-plate-shaped reinforcing coupling plates 52 and 52 extending in thewidth direction are provided between a lower surface of an intermediateportion of the flat plate 44 in the width direction and inner surfacesof downward extending parts 45 and 45 in the width direction in a statein which the reinforcing coupling plates 52 and 52 are spaced apart inthe forward and rearward direction.

In this example, a joining part 43 a disposed relatively forward isprovided to extend upward from both sides (both sides of the cutout 46)of a front end section of the reinforcing plate 42 in the widthdirection. The joining part 43 a is a portion of a lower surface of afront end section of the frame body 34 which is adjacent to a front sideof a circumferential slit 37 a, and is coupled to both side portions inthe circumferential direction which surround the axial slit (a firstslit) 36. A joining part 43 b disposed relatively rearward is providedto extend upward from a rear end section of the reinforcing plate 42.The joining part 43 b is coupled to a portion of a lower surface of arear end section of the frame body 34 which is adjacent to a rear sideof a rear end section of an axial slit 36. Alternatively and/oradditionally, the reinforcing bridge part 41 can have a differentconstitution from the above.

In this example, the outer column 11 a includes the above-describedreinforcing bridge part 41, and thus has high twist rigidity. Gaps (theslits) 47 and 47 with a substantially U shape (an angulated U shape)when viewed from the width direction (the second direction) are formedbetween the reinforcing bridge part 41 and the clamp parts 38 and 38.The gaps 47 and 47 have at least telescopic adjustment slots (axialslits, first slits, and first through holes) 21 a and 21 a extending inthe axial direction (an axial direction of the outer column 11 a and anaxial direction of a steering shaft 2 a) and circumferential slits (thesecond slits) 37 a and 37 b provided to be continuous with the slots 21a and 21 a and extending in a direction such that intersect the slots 21a and 21 a. The clamp parts 38 and 38 are provided adjacent to the slots21 a and 21 a. The slots 21 a and 21 a form spaces which are presentbetween distal end sections (lower end sections) of the clamp parts 38and 38 and upper surfaces of the reinforcing plate 42 (the flat plate44). An adjusting rod 24 a is inserted through the slots 21 a and 21 ain the width direction (the second direction).

The outer column 11 a has an acting surface (a first surface, a firstacting surface, a first abutting surface, and a torque transmissionsurface) 49 a and an acting surface (a second surface, a second actingsurface, a second abutting surface, and a torque transmission surface)49 b which are provided on two lateral surfaces thereof in the widthdirection. The acting surface 49 a and the acting surface 49 b arearranged to be spaced apart from each other in a first direction (afirst intersecting direction) serving as a direction which intersectsthe axial direction (the axial direction of the outer column 11 a andthe axial direction of the steering shaft 2 a). Furthermore, the clamppart 38 (and the acting surface 40) is arranged between the actingsurface 49 a and the acting surface 49 b in the first direction. In thisexample, the adjusting rod 24 a is arranged between the acting surface49 a and the acting surface 49 b in the first direction, and the actingsurface 40 of the clamp part 38 is arranged between the acting surface49 a and the adjusting rod 24 a in the first direction. Furthermore, theaxial slit 36 (the slot 21 a) is arranged between the acting surface 49a and the acting surface 49 b in the first direction. In this example,torque (a force in a twist direction) acting on the outer column 11 amay be transmitted to inner surfaces of support plates 22 a and 22 a inan upper bracket 17 a via the acting surface 49 a and the acting surface49 b.

In this example, the acting surface 49 a is arranged within a range ofan external form of an inner column 10 a in the first direction. Theacting surface 49 b is arranged outside of the range of the externalform of the inner column 10 a in the first direction. In addition, theacting surface 49 b is arranged outside of a range of an external formof a cylindrical body 35 of the outer column 11 a. Furthermore, in thefirst direction, the acting surface 49 a is arranged relatively close toa central axis of the inner column 10 a, and the acting surface 49 b isarranged relatively away from the central axis of the inner column 10 a.Ridge parts 50 a and 50 a are provided in a portion overlapping acentral axis of the outer column 11 a in the first direction (or thevertical direction) on portions on both sides of the outer column 11 a(the frame body 34) in the width direction to protrude outwardly in thewidth direction (the second direction). The ridge part 50 a is providedto extend to the outer column 11 a. The acting surfaces 49 a and 49 aare provided on distal ends (outer surfaces thereof in the widthdirection) of the ridge part 50 a. Ridge parts 50 b and 50 b areprovided on lower end sections of outer surfaces of the downwardextending parts 45 and 45 in the width direction to protrude outwardlyin the width direction (the second direction). The ridge part 50 b isprovided to extend in the axial direction of the outer column 11 a. Theacting surfaces 49 b and 49 b are provided on distal ends (outersurfaces in the width direction) of the ridge part 50 b. In other words,both of the acting surfaces 49 a and 49 b have a shape extending in theaxial direction of the outer column 11 a, and have a longer length thanthat of the clamp part 38 in the axial direction. For example, theacting surface 49 a and the acting surface 49 b have a flat surfaceshape. Additionally and/or alternatively, the acting surface 49 a andthe acting surface 49 b can have a shape other than the flat shape. Theacting surfaces 49 a and 49 b have a higher rigidity in the widthdirection (the second direction) than those of the clamp parts 38 and38. A plurality of (six in the illustrated example) depressed portions53 and 53 which are depressed inwardly in the width direction areprovided in intermediate portions in the vertical direction (above theridge part 50 b) on the outer surfaces of the downward extending parts45 and 45 in the width direction in a state in which the depressed parts53 and 53 are spaced apart from each other in the forward and rearwarddirection.

In this example, as shown in FIG. 36, in a state in which no externalforce is applied to the outer column 11 a (tightening has been released(a second state)), a width dimension Ha of the pair of acting surfaces49 a and 49 a provided on an upper side, a width dimension Hb of thepair of acting surfaces 49 b and 49 b provided on a lower side, and awidth dimension Hc of the acting surfaces 40 and 40 of the clamp parts38 and 38 are substantially the same (Ha=Hb=Hc). In other words, theacting surface 49 a, the acting surface 49 b, and the acting surface 40on one side in the width direction are located on the same virtualplane. Furthermore, the acting surface 49 a, the acting surface 49 b,and the acting surface 40 on the other side in the width direction arelocated on the same virtual plane. The acting surfaces 40 and 40 arearranged between the acting surfaces 49 a and 49 a and the actingsurfaces 49 b and 49 b in the first direction. Alternatively, the actingsurfaces 49 a and 49 a, the acting surfaces 49 b and 49 b, and theacting surfaces 40 and 40 can have a disposition relationship other thanthe above-described relationship. For example, when a clamping force ofthe clamp parts 38 and 38 needs to be increased and the like, the widthdimension Hc can be increased in comparison to the width dimension Haand the width dimension Hb in some cases (Hc>Ha=Hb).

In this example, as shown in FIG. 33, dimensions (X,Z) of the actingsurfaces 49 a and 49 b disposed on the upper side and the lower side inthe forward and rearward direction are larger than a dimension (Y) ofthe acting surface 40 in the forward and rearward direction (X>Y andZ>Y). In addition, the dimension (X) of the acting surface 49 a in theforward and rearward direction is substantially the same as thedimension (Z) of the acting surface 49 b in the forward and rearwarddirection (X≈Z). In other words, a distance from a central portion ofthe telescopic adjustment slot 21 a in the forward and rearwarddirection to a front edge of the acting surface 49 a is set to besubstantially the same as a distance from the central portion of theslot 21 a in the forward and rearward direction to a rear edge of theacting surface 49 a. The same applies to front edges and rear edges ofthe acting surface 49 b and the acting surface 40.

The acting surface 40 of the clamp part 38 may substantially have asymmetrical shape with respect to a predetermined symmetry axis, and mayby asymmetric with respect to the symmetry axis. Furthermore, in theaxial direction, a center of the clamp part 38 (and/or the center of theacting surface 40) may coincide with and be offset from centers of theacting surface 49 a and the acting surface 49 b. A shape and/or astructure of the clamp part 38 may be set to be offset with respect tothe acting surface 49 a and the acting surface 49 b in the axialdirection. For example, the center of the clamp part 38 (and/or thecenter of the acting surface 40) can be located in front of (or behind)the centers of the acting surface 49 a and the acting surface 49 b ofthe outer column 11 a. In the axial direction, the center of thetelescopic adjustment slot 21 a may coincide with and be offset from atleast one of the acting surface 49 a, the acting surface 49 b, and theacting surface 40. For example, the center of the acting surface 40 inthe clamp part 38 can be located in front of the center of the slot 21a. In this example, the acting surface 40 is offset in the axialdirection so that it is possible to make the acting surface 40 change anoperational force of an adjusting lever 26 a even when front and rearpositions of the steering wheel 1 have changed (refer to FIGS. 45 and46). To be specific, when the steering wheel 1 is maximally displacedtoward a rear side, a fitting margin of a rear end section of the innercolumn 10 a and a front end section of the outer column 11 a isrelatively short, and the acting surface 40 tightens a rear-end-sideportion of the inner column 10 a. In this case, since rigidity of therear-end-side portion of the inner column 10 a is lower than that of anintermediate portion thereof, a tightening reaction force thereof isrelatively low, and the operational force of the adjusting lever 26 a isrelatively low. Thus, the acting surface 40 is offset forward so thatthe intermediate portion with a higher rigidity than that of therear-end-side portion in the inner column 10 a is pressed, and thus ahigh tightening reaction force is obtained. Moreover, a change inrigidity of the inner column 10 a along with a positional adjustment ofthe front and rear position is relatively small and a change in thetightening reaction force is also small in a state in which the steeringwheel 1 is located relatively forward, and a fitting margin of the innercolumn 10 a and the outer column 11 a is large. In other words, a changein the operational force of the adjusting lever 26 a along with a changein the front and rear position of the steering wheel 1 is minimized overthe whole range due to the above-described offset.

In this example, upper end sections of the joining parts 43 a and 43 bin the reinforcing bridge part 41 are continuous with both end sectionsof the ridge parts 50 a and 50 b in the forward and rearward direction.Here, in this example, outer surfaces of the joining parts 43 a and 43 bin the width direction are located (offset) closer to insides in thewidth direction than the acting surface 49 a, the acting surface 49 b,and the acting surface 40. In this case, the inner surfaces of thesupport plates 22 a and 22 a in the upper bracket 17 a can be set not tosubstantially come into contact with the outer surfaces of the joiningparts 43 a and 43 b in the width direction.

Note that, in this example, particularly with regard to a basicconstitution of the outer column 11 a, a brief description from anotherviewpoint will be provided. A pair of sandwiched plates are integrallyformed with the outer column 11 a in a state in which the axial slit 36is sandwiched from both sides thereof in the width direction by thesandwiched plates, and distal end sections (lower end sections) of thesandwiched plates are joined to the outer column 11 a in this example(by a portion corresponding to the reinforcing plate 42). Moreover,outer surfaces of the sandwiched plates in the width direction are setas tightening surfaces with a substantially flat surface shape. The gaps(the slits) 47 and 47 with the substantially U shape which communicatewith an inner circumferential surface of the outer column 11 a areformed in substantially central positions of the tightening surfaces,and portions enclosed by the gaps 47 and 47 are set as the clamp parts38 and 38. Moreover, upper sides and lower sides of the tighteningsurfaces are set as the acting surfaces 49 a and 49 b.

As shown in FIGS. 28, 29, 30, and 31, the upper bracket (the supportbracket) 17 a is constituted of, for example, a metal plate of asteel-based alloy, an aluminum-based alloy, and the like with sufficientrigidity. The upper bracket 17 a includes an attachment plate 58 and thepair of support plates 22 a and 22 a. The attachment plate 58 isnormally supported on a vehicle body 15 a. The attachment plate 58 isconfigured to be detached forward such that a forward displacement ofthe outer column 11 a is allowed on the basis of an impact such as asecondary collision. A pair of locking cutouts 59 and 59 are formed in arear edge of the attachment plate 58 in a state in which the lockingcutouts 59 and 59 are open. Locking capsules 18 a and 18 a fixed to thevehicle body 15 a using fixing members such as bolts or studs are lockedinto the locking cutouts 59 and 59.

The support plates 22 a and 22 a are provided to hang from theattachment plate 58. Furthermore, the support plates 22 a and 22 a areprovided to be parallel to each other in a state in which the front endsection (the frame body 34 and the reinforcing bridge part 41) of theouter column 11 a is sandwiched from both sides thereof in the widthdirection by the support plates 22 a and 22 a. The pair of supportplates 22 a and 22 a are arranged on both sides of the outer column 11 ain the width direction (the second direction). At least tilt adjustmentslots (second through holes) 23 a and 23 a extending in the verticaldirection (the first direction) are formed in the support plates 22 aand 22 a. The slots 23 a and 23 a are provided in opposing positions(positions matching each other) in the width direction. Furthermore, theslots 23 a and 23 a are provided to match portions of the telescopicadjustment slots 21 a and 21 a in the forward and rearward direction.The slots 23 a and 23 a have long axes in the vertical direction (thefirst direction). The support plates 22 a and 22 a are arranged to beable to tighten the outer column 11 a (the steering column 4 a) using atightening mechanism 80. The tightening mechanism 80 includes theadjusting rod 24 a, an adjusting nut 25, the adjusting lever 26 a, andthe like (refer to FIG. 28). The adjusting rod 24 a is inserted throughthe telescopic adjustment slots 21 a and 21 a and the tilt adjustmentslots 23 a and 23 a in the width direction.

The adjusting rod 24 a includes an anchor part disposed on one endsection thereof, a male screw part formed at the other end sectionthereof, and a shaft part formed on an intermediate portion in the widthdirection (an axial direction of the adjusting rod 24 a; the seconddirection). The adjusting rod 24 a is disposed to be inserted throughthe telescopic adjustment slots 21 a and 21 a and the tilt adjustmentthe slots 23 a and 23 a. The anchor part is provided on one end side ofthe adjusting rod 24 a in the width direction. The anchor part isrelatively non-rotatably engaged with the tilt adjustment slot 23 aformed in one support plate 22 a. A cam device 69, which is constitutedof a driving-side cam and a driven-side cam, and the adjusting lever 26a are provided in the vicinity of a portion of the adjusting rod 24 a(the shaft part) which protrudes in the width direction from an outersurface of the other support plate 22 a in the width direction. A nut 70is screwed on the male screw part. The driving-side cam of the camdevice 69 is rotated relative to the driven-side cam on the basis of arocking operation of the adjusting lever 26 a in the tighteningmechanism 80 so that a width dimension (a dimension of the adjusting rod24 a in the axial direction) of the cam device 69 is expandable andcontractable.

In this example, the steering device includes a steering lock deviceserving as a type of a vehicle anti-theft device. In the outer column 11a, a locking through hole 33 a is formed in the cylindrical body 35 topass through in a radial direction. A fixed part 71 configured tosupport and fix a lock unit (not shown) is provided on a portion in anouter circumferential surface of the cylindrical body 35 which isshifted from the locking through hole 33 a in the circumferentialdirection. A pair of attachment flanges 72 and 72 are provided on thefixed part 71. The lock unit is supported by and fixed to the vicinityof the locking through hole 33 a using the attachment flanges 72 and 72,and a key lock collar (not shown) is externally-fitted (press-fitted) tothe steering shaft 2 a. The key lock collar is arranged at a portion atwhich phases of the key lock collar and the lock unit coincide with eachother at a part of the steering shaft 2 a in the axial direction. Whenthe ignition key is switched off in the lock unit, a distal end sectionof a lock pin in the lock unit is displaced toward an inner diameter ofthe outer column 11 a and is engaged with a key lock depressed portionformed in an outer circumferential surface of the key lock collar. Thus,the steering shaft 2 a cannot be substantially rotated. That is to say,the key lock depressed portion is engaged with the distal end section ofthe lock pin in a state in which the steering shaft 2 a cannot besubstantially rotated at a time of key locking. A predetermined value(for example, a value defined by key lock regulations; a limit value)used to release a non-rotatable state is set for the lock unit. Rotationof the steering shaft 2 a by a force with an extent that the steeringwheel 1 (refer to FIG. 45) is operated by only a normal driving postureis prevented. When the steering wheel 1 (refer to FIGS. 45 and 46) isrotated using a force greater than or equal to the predetermined value,the steering shaft 2 a is allowed to rotate with respect to the key lockcollar and the steering column 4 a.

In this example with the above-described constitution, the tighteningmechanism 80 has a first state (a first form and a first mode) in whichthe outer column 11 a (the steering column 4 a) is tightened through theupper bracket (the support bracket) 17 a, and a second state (a secondform and a second mode) in which the tightening is released.

When the steering wheel 1 is moved to a desired position and then heldat the desired position, the adjusting lever 26 a of the tighteningmechanism 80 is rocked (turned) about the adjusting rod 24 a in apredetermined direction (generally, upward). As a result, the widthdimension of the cam device 69 increases and an interval between theinner surfaces of the support plates 22 a and 22 a decreases. The actingsurfaces 49 a and 49 a, the acting surfaces 49 b and 49 b, and theacting surfaces 40 and 40 of the clamp parts 38 and 38 are pressed bythe inner surfaces of the support plates 22 a and 22 a. Intermediateportions of the support plates 22 a and 22 b in the vertical directionand the clamp parts 38 and 38 are bent (elastically deformed) inwardlyin the width direction (toward the axis center), and the outercircumferential surface of the inner column 10 a is accordinglyelastically sandwiched (held) (is tightened in the tightening direction(the second direction)). Thus, the steering wheel 1 is held in theadjusted position.

On the other hand, when a position of the steering wheel 1 is adjusted,the adjusting lever 26 a is rocked (turned) in an opposite direction(generally, downward) to the predetermined direction. As a result, thewidth dimension of the cam device 69 decreases and the interval betweenthe inner surfaces of the support plates 22 a and 22 a increases. Sincea pressing force (a tightening force) by the support plates 22 a and 22a decreases, a width dimension between the clamp parts 38 and 38elastically increases and a holding force of the outer circumferentialsurface of the inner column 10 a increases (the tightening is released).In the second state, the front and rear position and the verticalposition of the steering wheel 1 can be adjusted in a range in which theadjusting rod 24 a can be moved within the telescopic adjustment slots21 a and 21 a and the tilt adjustment slots 23 a and 23 a.

In the steering device of this example, the acting surfaces 49 a and 49a, the acting surfaces 49 b and 49 b, and the acting surfaces 40 and 40of the clamp parts 38 and 38 are provided on both sides of the outercolumn 11 a in the width direction (the second direction and thetightening direction). The acting surfaces 49 a and 49 a and the actingsurfaces 49 b and 49 b are directly pressed onto the support plates 22 aand 22 a of the upper bracket 17 a in a tightened state (the firststate). The acting surfaces 40 and 40 of the clamp parts 38 and 38 areindirectly pressed onto the support plates 22 a and 22 a in thetightened state (the first state). The acting surface (the firstsurface) 49 a, the acting surface (the second surface) 49 b, and theacting surface (the third surface) 40 are substantially independent ofeach other. The acting surfaces 49 a and 49 a and the acting surfaces 49b and 49 b are provided on the frame body 34 of the outer column 11 a,and positions thereof with respect to the inner column 10 a do notsubstantially change, or amounts of displacement thereof are slightwhile transitioning from the released state (the second state) to thetightened state (the first state). A position of the acting surface 40of the clamp part 38 with respect to the inner column 10 a changes witha relatively large amount of displacement (is displaced toward the innercolumn 10 a) (a displacement surface) while transitioning from thereleased state (the second state) to the tightened state (the firststate). In the first state, the outer column 11 a and the support plates22 a and 22 a are coupled to each other by a force acting on the actingsurfaces 49 a and 49 a mainly at a position near the central axis of theouter column 11 a. In the first state, the outer column 11 a and thesupport plates 22 a and 22 b are coupled to each other by a force actingon the acting surface 49 b and 49 b mainly at a position away from thecentral axis of the outer column 11 a. In the first state, the innercolumn 10 a is held mainly in the outer column 11 a through the clamppart 38 by a force acting on the acting surfaces 40 and 40. Therefore,in the steering device in this example, securing strength of the outercolumn 11 a and securing a holding force of the inner column 10 a aresimultaneously and independently realized, and a position adjustingmechanism with high stability is provided.

As shown in FIGS. 29, 30, and the like, in the steering device in thisexample, the acting surface 40 of the clamp part 38 and the actingsurfaces 49 a and 49 b are separately independently provided on bothsides of the outer column 11 a in the width direction. The clamp parts38 and 38 are used for elastically sandwiching the outer circumferentialsurface of the inner column 10 a. On the other hand, for example, whenthe steering wheel 1 is operated by a large force while the steeringlock device is being operated and the like, torque acting on the outercolumn 11 a is transmitted to the inner surfaces of the support plates22 a and 22 a of the upper bracket 17 a via the acting surfaces 49 a and49 b. The clamp parts 38 and 38 may be adopted as long as the clampparts 38 and 38 can exhibit only a function of sandwiching the innercolumn 10 a. For this reason, it is not necessary to set a high strengthhigher than or equal to that which is necessary. Therefore, in thesteering device in this example, desired bending characteristics such asgreatly bending the clamp parts 38 and 38 in the width direction can beset for the clamp parts 38 and 38. On the other hand, the actingsurfaces 49 a and 49 b may be adopted as long as the acting surfaces 49a and 49 b can exhibit only a function of transmitting the torque. Forthis reason, it is not necessary to greatly bend sections in which theacting surfaces 49 a and 49 b in the outer column 11 a are installed inthe width direction. Therefore, according to the steering device in thisexample, securing strength of the outer column 11 a can be independentlycompatible with securing the holding force of the inner column 10 a.

Alternatively, in the steering device in this example, the innersurfaces of the support plates 22 a and 22 a are brought into contactwith (pressed by) the acting surfaces 49 a and 49 b to hold the steeringwheel 1 at a desired position. At this time, the clamp parts 38 and 38are bent through the inner surfaces of the support plates 22 a and 22 a.In the outer column 11 a, the acting surfaces 49 a and 49 b are actuallyindependent from the acting surface 40 of the clamp part 38, and theportions in which the acting surfaces 49 a and 49 b are installed havesufficiently high rigidity (bending rigidity and bent characteristics)when compared to the clamp part 38. Furthermore, the acting surface 49 aand the acting surface 49 b are arranged to be spaced apart from eachother in the first direction which intersects the second direction (thetightening direction). Particularly, a position of the acting surface 49b is outside of the range of the external form of the inner column 10 ain the first direction and is outside of a range of an external form ofthe cylindrical body 35 of the outer column 11 a. For this reason, thetorque acting on the outer column 11 a is absorbed through the actingsurfaces 49 a and 49 b, and thus the torque can be prevented from beingtransmitted to the clamp part 38.

In the steering device in this example, the outer surfaces of thejoining parts 43 a and 43 b in the width direction are located (offset)closer to an inside in the width direction than the acting surfaces 49 aand 49 b and the acting surfaces 40 and 40. For this reason, whentransition is performed from a state in which the position of thesteering wheel 1 can be adjusted (the second state) to a state in whichthe position of the steering wheel 1 can be held (the first state), theinner surface of the support plate 22 a does not come into contact withthe outer surfaces of the joining parts 43 a and 43 b in the widthdirection. In other words, the transition from the second state to thefirst state is performed, and the inner surfaces of the support plates22 a and 22 a mainly press the acting surfaces 49 a and 49 a, the actingsurfaces 49 b and 49 b, and the acting surfaces 40 and 40. For thisreason, an area of a portion pressed by the inner surface of the supportplate 22 a (abutting areas of the acting surface 49 a, the actingsurface 49 b, and the acting surface 40 on the support plate 22 a) isconstant (or falls within a predetermined range) regardless of theposition of the steering wheel 1 in the forward and rearward direction.As a result, when the position of the steering wheel 1 in the forwardand rearward direction is adjusted, a change in tightening torque of theadjusting lever 26 a is suppressed to be small. Therefore, in theoperation of the adjusting lever 26 a, stable operability can beobtained.

Fourth Example of Embodiment

A fourth example according to the embodiment of the present inventionwill be described with reference to FIGS. 39 and 40. In the followingdescription, constituent parts which are the same as or equivalent tothose of the above-described will be denoted with the same referencenumerals, and description thereof will be simplified or omitted.

Particularly, a structure of clamp parts 38 and 38 in a steering devicein this example different from that of the third example in theabove-described embodiment. In this example, like in the third example,the clamp parts 38 and 38 are provided by forming axial slits 36 (slots21 a and 21 a) in both sides of an outer column 11 a in a widthdirection, slits 37 a and 37 b in a direction which intersects an axialdirection, and the like to be continuous. The clamp parts 38 and 38 havea cantilever structure with a fixed end extending in the axialdirection.

In this example, unlike the third example, cross-sectional structuresbetween central portions and end sections of the clamp parts 38 and 38in the axial direction substantially differ. Firstly, a region near acenter of the clamp part 38 in the axial direction has a thinnerthickness than regions near ends thereof in the axial direction. Forexample, the two regions (a front section 81 a and a rear section 81 b)near the ends of the clamp part 38 in the axial direction uniformly havea first thickness. The region (an intermediate portion 81 c) near thecenter of the clamp part 38 in the axial direction uniformly has asecond thickness thinner than the first thickness. Secondly, reinforcingribs 51 are provided on the portions (the front section 81 a and therear section 81 b) near both ends of the clamp part 38 in the axialdirection, and a reinforcing rib is not provided on the region (theintermediate portion 81 c) near the center thereof in the axialdirection. Alternatively and/or additionally, the clamp part 38 can haveanother cross-sectional structure.

As described above, the clamp part 38 has a cross-sectional structurewhich partially contributes to low rigidity in a portion (theintermediate portion 81 c) near the center thereof. Furthermore, theclamp part 38 has a cross-sectional structure which partiallycontributes to high rigidity in the portions (the front section 81 a andthe rear section 81 b) near both ends thereof in the axial direction. Asa result, in the clamp part 38 in this example, rigidity (bendingrigidity and bending characteristics) of the regions (the front section81 a and the rear section 81 b) near the end sections which are releasedare controlled so that the rigidity thereof is the same as that of theportion (the intermediate portion 81 c) near the portion near the centerthereof. In other words, the clamp part 38 has a generally substantiallyuniform rigidity distribution in the axial direction.

As described above, when a front and rear position of a steering wheel 1(refer to FIG. 46) changes in the steering device, a position of anadjusting rod 24 a (refer to FIG. 28) with respect to an outer column 11a in the axial direction changes. In other words, in a referenceposition, the adjusting rod 24 a is located in a center of the slot 21 ain the axial direction. In this case, a tightening force of a tighteningmechanism 80 (refer to FIG. 28) is exerted mainly on a central positionof the clamp part 38. When the steering wheel 1 is located relativelyrearward, the adjusting rod 24 a inserted through the slot 21 a of theouter column 11 a is located ahead of the center of the slot 21 a. Inthis case, the tightening force is exerted mainly on a relativelyforward position of the clamp part 38. When the steering wheel 1 islocated relatively forward, the adjusting rod 24 a is located fartherrearward than the center of the slot 21 a. In this case, the tighteningforce is exerted mainly on a relatively rearward position of the clamppart 38.

In this example, a change in operational force of the adjusting lever 26a (refer to FIG. 28) in the tightening mechanism 80 is minimized on thebasis of the substantially uniform rigidity distribution of the clamppart 38 even when the front and rear position of the steering wheel 1changes. In other words, the steering device in this example provides astable operation feeling with respect to an operation of the adjustinglever 26 a.

Here, in this example, the clamp part 38 has a substantial symmetricalshape and symmetrical structure with respect to a symmetry axis W alonga first direction which intersects the axial direction. In the clamppart 38, the two end regions (the front section 81 a and the rearsection 81 b) with the first thickness have a substantially symmetricalstructure with respect to the symmetry axis W. The center region (theintermediate portion 81 c) with the second thickness also has asubstantially symmetrical structure with respect to the symmetry axis W.Furthermore, distances between the reinforcing ribs 51 arranged on aportion (the front section 81 a) near one of the ends and the symmetryaxis W are substantially the same as those of the reinforcing ribs 51arranged on a portion (the rear section) near the other end.

In this example, an acting surface 40 of the clamp part 38 has asubstantially symmetrical shape with respect to the symmetry axis W. Inother words, a center of the acting surface 40 in the axial direction islocated on the symmetry axis W. In addition, in this example, centers ofan acting surface 49 a and an acting surface 49 b in the outer column 11a in the axial direction coincide with the center of the clamp part 38.For example, the centers of the acting surface 49 a and the actingsurface 49 b in the axial direction coincide with a center of the actingsurface 40 in the clamp part 38.

Alternatively, a shape and/or a structure of the clamp part 38 may beasymmetric with respect to the symmetry axis W. Alternatively, the shapeand/or the structure of the clamp part 38 may be provided to be offsetfrom the acting surface 49 a and the acting surface 49 b in the axialdirection like in the third example. In this case, for example, thecenter of the clamp part 38 (and/or the center of the acting surface 40)can be set to be located in front of (or to the rear of) the centers ofthe acting surface 49 a and the acting surface 49 b of the outer column11 a. Furthermore, in the axial direction, a center of the telescopicadjustment slot 21 a may coincide with and may be offset from at leastone of the centers of the acting surface 49 a, the acting surface 49 b,and the acting surface 40.

Fifth Example of Embodiment

A fifth example according to the embodiment of the present inventionwill be described with reference to FIGS. 41 to 44. In the followingdescription, constituent parts which are the same as or equivalent tothose of the above-described will be denoted with the same referencenumerals and description thereof will be simplified or omitted.

Particularly, a structure of a portion receiving a tightening force in asteering device in this example is different from that of the thirdexample in the above-described embodiment. In this example, like in thethird example, an outer column 11 a has an acting surface 49 a and anacting surface 49 b provided on two sides thereof in a width direction.Furthermore, the outer column 11 a further includes a clamp part 38configured to sandwich an inner column 10 a. The acting surface 49 a andthe acting surface 49 b are arranged to be spaced apart from each otherin a first direction which intersects an axial direction. An actingsurface 40 of the clamp part 38 is arranged between the acting surface49 a and the acting surface 49 b in the first direction. The actingsurface 40 of the clamp part 38 is provided independently from theacting surface 49 a and the acting surface 49 b. Furthermore, the actingsurface 49 a and the acting surface 49 b also have a mutuallyindependent relationship. The acting surface 49 a and the acting surface49 b are provided on a frame body 34 of the outer column 11 a, andpositions thereof with respect to the inner column 10 a do notsubstantially change, or amounts of displacement thereof are slightwhile transitioning from a released state (a second state) to atightening state (a first state). The acting surface 40 of the clamppart 38 is a displacement surface by which the position thereof withrespect to the inner column 10 a changes (is displaced toward the innercolumn 10 a) while transitioning from the released state (the secondstate) to the tightening state (the first state).

In this example, unlike the third example, the outer column 11 a furtherhas restriction surfaces (seating surfaces and fourth surfaces) 84configured to restrict an amount of tightening which is provided on twosides thereof in the width direction. Each of the restriction surfaces84 is provided on the frame body 34 of the outer column 11 a. Portionsof the outer column 11 a in which the restriction surfaces 84 areprovided have a higher rigidity (bending rigidity and bendingcharacteristics) than that of the clamp part 38. A position of therestriction surfaces 84 with respect to the inner column 10 a does notsubstantially change while transitioning from the released state (thesecond state) to the tightening state (the first state). Even when therestriction surfaces 84 are slightly displaced, an amount ofdisplacement thereof is set to be sufficiently lower than an amount ofdisplacement of the acting surface 40 of the clamp part 38. Furthermore,the restriction surfaces 84 are provided to extend in the axialdirection to have the same lengths as the acting surface 40 in the axialdirection. For example, the restriction surfaces 84 have a flat surfaceshape. Additionally and/or alternatively, the restriction surfaces 84can have a shape other than the flat shape. For example, the restrictionsurfaces 84 are arranged between the acting surface 40 and the actingsurface 49 b in the first direction. Alternatively and/or additionally,the restriction surfaces 84 can be disposed between the acting surface49 a and the acting surface 40 in the first direction. Furthermore, therestriction surface 84 is arranged adjacent to an axial slit 36 and/or aslot 21 a for an adjusting rod 24 a (refer to FIG. 28) in the firstdirection. Alternatively and/or additionally, the restriction surface 84can be disposed adjacent to a circumferential slit 37 a and/or acircumferential slit 37 b.

In this example, the restriction surface 84 is provided independentlyfrom the acting surface 49 a, the acting surface 49 b, and the actingsurface 40. Furthermore, the restriction surface 84 has a surface heightsubstantially lower in the width direction (a tightening direction and asecond direction) than those of the acting surface 49 a, the actingsurface 49 b, and the acting surface 40. In other words, as shown inFIG. 42, in a state in which the tightening is released (the secondstate), a width dimension Hd of the restriction surfaces 84 and 84 issmaller than a width dimension Hc of the acting surfaces 40 and 40 ofthe clamp part 38 (Hc>Hd). That is to say, in the second direction, agap Gp corresponding to an amount of tightening is provided between theacting surface 40 and the restriction surface 84. Note that, in thestate in which the tightening is released (the second state), a widthdimension Ha of the acting surfaces 49 a and 49 a, a width dimension Hbof the acting surfaces 49 b and 49 b, and the width dimension Hc of theacting surfaces 40 and 40 are substantially the same (Ha=Hb=Hc).Alternatively, in the state in which the tightening is released (thesecond state), the width dimension Hc of the acting surfaces 40 and 40is larger than the width dimension Ha of the acting surfaces 49 a and 49a and the width dimension Hb of the acting surfaces 49 b and 49 b(Hc>Ha=Hb). Other constitutions can be the same as those of theabove-described fourth example of the embodiment.

In this example, the restriction surface 84 is arranged between theacting surface 49 a and the acting surface 49 b in the first direction.In other words, the acting surface 40 of the clamp part 38 and therestriction surface 84 are arranged between the acting surface 49 a andthe acting surface 49 b. For example, in the first direction, a distancebetween the restriction surface 84 and the center of the slot 21 a (anaxis center of the adjusting rod 24 a) can be set to be comparable tothat of the acting surface 40.

In a tightening mechanism 80, an upper bracket 17 a is bent due to anoperation of the adjusting lever 26 a, and thus the interval between thesupport plates 22 a and 22 a is reduced while transitioning from thereleased state (the second state) to the tightening state (the firststate). As a result, the inner surface of the support plate 22 a is incontact with the acting surface (the first surface) 49 a, the actingsurface (the second surface) 49 b, and the acting surface (the thirdsurface) 40. After that, the interval between the support plates 22 aand 22 a can be further reduced due to a further operation of theadjusting lever 26 a.

In the steering device in this example, amounts of inward displacement(amounts of inward bending) of upper brackets 17 a and 17 a arerestricted by the restriction surfaces (fourth surfaces) 84 and 84provided on the frame body 34 of the outer column 11 a. After thesupport plate 22 a comes into contact with the acting surface 40 of theclamp part 38, the acting surface 40 pressed by the support plate 22 ais displaced inward in the width direction (toward the axis center ofthe outer column 11 a). After that, when the interval between thesupport plates 22 a and 22 a has a predetermined value, the innersurface of the support plate 22 is in contact with the restrictionsurface 84. The restriction surface 84 is not substantially displacedeven when the restriction surface 84 is pressed by the support plate 22a. For this reason, after the support plate 22 a is in contact with therestriction surface 84, the displacement (the bending) of the supportplate 22 a toward the axis center of the outer column 11 a is forciblystopped. Accordingly, the displacement (the bending) of the clamp part38 toward the axis center of the outer column 11 a is also stopped. Inother words, after the support plate 22 a comes into contact with therestriction surface 84, an increase in a holding force with respect tothe inner column 10 a by the clamp part 38 is prevented even when theadjusting lever 26 a is further operated.

As shown in FIG. 44(A), a holding force (a telescopic holding force) ofthe clamp part 38 with respect to the inner column 10 a increases alongwith an increase in an operational force (lever operating force) of theadjusting lever 26 a. Simultaneously, a tilt holding force(substantially corresponding to a force by which the support plates 22 aand 22 a hold the outer column 11 a) also increases. When the supportplate 22 a corresponds to the restriction surface 84 (the leveroperating force=LF2), the tilt holding force increases, but thetelescopic holding force is kept constant (HF2) even when the leveroperating force increases after that. Therefore, in the case of thesteering device in this example, excess tightening with respect to theinner column 10 a is avoided, and thus the steering device isadvantageous, for example, in terms of manufacturing management.

For example, in the steering device in this example, a telescopicholding force with respect to a predetermined lever operating forcechanges in accordance with rigidity of the upper bracket 17 a. In otherwords, when the rigidity of the upper bracket 17 a is relatively high,the telescopic holding force with respect to the predetermined leveroperating force is relatively low. If the restriction surface 84 is notprovided to the outer column 11 a, as shown in FIG. 44(B), a designrequirement range of the lever operating force tends to become narrowerthan a line management range with respect to a standard in which anupper limit of the telescopic holding force is restricted. On the otherhand, like in this example, when the restriction surface 84 is providedon the outer column 11 a, as shown in FIG. 44(A), the design requirementrange of the lever operating force can substantially match a linemanagement range. As a result, according to the steering device in thisexample, stable manufacturing management is realized.

Note that constituent elements in the above-described embodiments can beappropriately combined. Furthermore, some of the constituent elementsmay not be used in some cases. This disclosure relates to all novel andnon-obvious features and aspects of variously disclosed embodimentsthemselves and various combinations and sub-combinations with otherembodiments. The disclosed details and methods are not limited to anyparticular aspect, technique, or combination, and the disclosed detailsand methods are not requires to have one or more particular advantagesor solve a particular problem.

The outer column is not limited to a structure obtained by joining aframe body made of a light alloy and a cylindrical body made of aniron-based alloy, and the whole outer column may be constituted of amember made of a light alloy such as an aluminum-based alloy and amagnesium-based alloy. The steering device may have a structureincluding both mechanisms of a tilt adjustment mechanism and atelescopic adjustment mechanism, and may have a structure including onlyone of the telescopic adjustment mechanism and the tilt mechanism. Aformation position of the axial slit and a formation position of thereinforcing bridge part may be opposite to (formed above) those of theabove-described aspects in the vertical direction. When the interval ofthe inner surfaces of the pair of support plates is reduced, the endsurfaces of the projecting plate in the width direction may beconfigured to be pressed without the roller (a rotating member) beingpressed. In this case, for example, the support plate can be pressed tobe bent inward in the width direction between the upper and lower actingsurfaces. The steering device may not include the steering lock device.In this case, as the torque acting on the outer column, for example, areaction force during steering, particularly, a steering reaction forceincreases when a power assist mechanism is attached. The acting surface(the pressed surface) of the clamp part may be configured not to besubstantially separated from another acting surface.

In the embodiment, the steering device includes the steering column, thesupport bracket, and the adjusting rod. The steering column isconfigured by loosely fitting (externally engaging) the front endsection of the outer column disposed on the rear side of the steeringdevice to the rear end section of the inner column disposed on the frontside of the steering device such that relative displacement in the axialdirection is possible. Moreover, the support bracket is supported by andfixed to the vehicle body, and includes the pair of support platessandwiching the front end section of the outer column from both sides ofthe outer column in the width direction. Moreover, the adjusting rod isdisposed in a state in which the adjusting rod is inserted through afirst through hole (for example, the telescopic adjustment slot or acircular hole) formed in the front end section of the outer column andsecond through holes (for example, the tilt adjustment slots or circularholes) formed in the support plates in the width direction. Note that,when the steering device is implemented using a structure including thetelescopic mechanism, the first through hole is set to be a telescopicadjustment slot which is elongated in the axial direction, and when thesteering device is implemented using a structure including the tiltmechanism, the second through holes are set to be tilt adjustment slotswhich are elongated in the vertical direction. On the other hand, whenonly any one of the telescopic mechanism and the tilt mechanism isincluded, and the other mechanism is not included, only one of thethrough holes is set to be a slotted hole/elongated hole, and the otherthrough hole is set to be a circular hole.

In one embodiment, at least one or more slits extending in the axialdirection of the outer column are formed in the front end section of theouter column. Note that a shape of the slit can be formed in a straightlinear shape extending in the axial direction, and can be formed in asubstantially U shape (an angulated U shape) extending in the samedirection in the circumferential direction (the vertical direction) fromboth end sections of the slit in the axial direction (the forward andrearward direction). Moreover, the pair of clamp parts in the outercolumn, which are adjacent to the slit in the circumferential direction,bent when the interval between the inner surfaces of the support platesis reduced, and elastically sandwich the outer circumferential surfaceof the inner column, are provided on both sides of the outer column inthe width direction. In addition, the first surface and the secondsurface configured to transmit torque acting on the outer column (forexample, torque input to the steering wheel and transmitted via thesteering shaft, the key lock collar, and the lock unit) to the innersurfaces of the support plates are formed on portions of both sides ofthe outer column in the width direction which are higher in rigidity inthe width direction than portions which sandwich the clamp part, arespaced apart from each other in the vertical direction, and in which theclamp part is provided. Moreover, when transition from the state inwhich the position of the steering wheel can be adjusted to the state inwhich the position of the steering wheel can be held is performed, theinner surfaces of the support plates is in contact with only the outersurfaces of the clamps and the acting surfaces.

In one example, end sections of the acting surfaces in the forward andrearward direction are continuous in the vertical direction due to thelateral surfaces in the width direction of the pair of joining partsextending in the vertical direction. Moreover, the lateral surfaces ofthe joining part in the width direction are offset further inward in thewidth direction than the acting surfaces.

EXPLANATION OF NUMERALS AND CHARACTERS

-   -   1 Steering wheel    -   2, 2 a Steering shaft    -   3 Steering wheel    -   4, 4 a Steering column    -   5 Steering force auxiliary device    -   6 Tie rod    -   7 Steering gear unit    -   8 Inner shaft    -   9, 9 a Outer shaft    -   10, 10 a Inner column    -   11, 11 a, 11 b Outer column    -   12, 12 a Gear housing    -   13 Output shaft    -   14, 14 a Lower bracket    -   15, 15 a Vehicle body    -   16, 16 a Tilt shaft    -   17, 17 a Upper bracket (support bracket)    -   18, 18 a Locking capsule    -   19 Slit    -   20 Clamp part    -   21, 21 a, 21 b Slot (telescopic adjustment slot, slit)    -   22, 22 a Support plate    -   23, 23 a Slot (tilt adjustment slot)    -   24, 24 a Adjusting rod    -   25 Adjusting nut    -   26, 26 a Adjusting lever    -   27, 27 a Anchor part    -   28 Universal joint    -   29 Intermediate shaft    -   30 Universal joint    -   31 Shaft (input shaft)    -   32, 32 a Electric motor    -   33, 33 a Locking through hole    -   34, 34 a Frame body (main body, sandwiched portion main body)    -   35 Cylindrical body (cylindrical member)    -   36 Axial slit (first slit)    -   37 a, 37 b, 37 c, 37 d Circumferential slit (second slit)    -   38, 38 a Clamp part    -   39 Projecting part (projecting plate)    -   40 Acting surface (third surface, pressed surface)    -   41 Reinforcing bridge part (reinforcing part)    -   42 Reinforcing plate    -   43 a, 43 b Joining part    -   44 Flat plate    -   45 Outer flat plate (downward extending part)    -   46 Step part (cutout)    -   47 Gap    -   48 Roller travel groove    -   49 a, 49 c Acting surface (first surface, torque transmission        surface)    -   49 b, 49 d Acting surface (second surface, torque transmission        surface)    -   50, 50 a, 50 b Ridge part    -   51 Reinforcing rib    -   51 a, 51 b Depressed part    -   52 Reinforcing coupling plate    -   52 a, 52 b Continuous flat surface    -   53 Locking groove (depressed portion)    -   54 Slide member    -   55 Slide part main body    -   56 Support arm    -   57 Depressed part    -   58 Attachment plate    -   59 Locking cutout    -   60 Locking groove    -   61 Through hole    -   62 Shaft part    -   63 Roller    -   64 Roller main body    -   65 collar    -   66 Through hole    -   67 Flange    -   68 Thin part    -   69 Cam device    -   70 Nut    -   71 Fixed part    -   71A Bent part    -   72 Attachment flange    -   72A Tilt spring    -   73 Lock unit    -   74 Key lock collar    -   75 Lock pin    -   76 Key lock depressed part    -   80 Tightening mechanism    -   81 a Front section    -   81 b Rear section    -   81 c Intermediate portion    -   84 Restriction surface (fourth surface, seating surface)

The invention claimed is:
 1. A steering device comprising: a steeringcolumn including an outer column and an inner column, a part of theinner column being enclosed by the outer column; a support bracketattachable to a vehicle body to support the steering column; and atightening mechanism having a first state in which the steering columnis tightened with the support bracket and a second state in which thetightening is released, wherein the outer column includes: a firstsurface and a second surface arranged spaced apart from each other in afirst direction, which intersects an axial direction, and such that thefirst surface and the second surface are pressed by the support bracketin the first state; a clamp part having a third surface, the thirdsurface being provided independently from the first surface and thesecond surface, and such that the third surface is pressed by thesupport bracket in the first state; and a slit provided between thefirst surface and the second surface in the first direction, and theslit includes: a first slit extending in at least the axial direction;and a second slit provided to be continuous with the first slit andextending in a direction which intersects the first slit, the first slitand the second slit being arranged surrounding the third surface.
 2. Thesteering device according to claim 1, wherein the third surface isarranged between the first surface and the second surface in the firstdirection.
 3. The steering device according to claim 1, wherein thetightening mechanism includes an adjusting rod, the adjusting rod isarranged between the first surface and the second surface in the firstdirection, and the third surface is arranged between the first surfaceand the adjusting rod in the first direction.
 4. The steering deviceaccording to claim 1, wherein the clamp part is provided adjacent to theslit.
 5. The steering device according to claim 1, wherein the supportbracket includes a pair of support plates arranged, respectively, onboth sides of the outer column in a second direction which intersectsthe axial direction and the first direction, and the first surface, thesecond surface, and the third surface are provided on each side of theouter column in the second direction.
 6. The steering device accordingto claim 1, wherein the first surface is located inside, in the firstdirection, a contour of the inner column, the second surface is locatedoutside, in the first direction, the contour of the inner column, andthe outer column further includes a reinforcing part, an end portion ofwhich is arranged adjacent the second surface, and such that thereinforcing part is bridged between both sides of the outer column in asecond direction which intersects the axial direction and the firstdirection.
 7. The steering device according to claim 1, wherein thethird surface is directly or indirectly pressed by the support bracketin the first state.
 8. The steering device according to claim 1, whereinthe clamp part has a symmetrical structure with respect to a symmetryaxis along the first direction.
 9. The steering device according toclaim 1, wherein the clamp part has substantially differentcross-sectional structures between a central portion and an end portionin the axial direction.
 10. The steering device according to claim 1,wherein the outer column further has a fourth surface that is providedindependently from the first surface, the second surface, and the thirdsurface, and that has a surface height substantially lower than those ofthe first surface, the second surface, and the third surface.
 11. Thesteering device according to claim 10, wherein the fourth surface isarranged between the first surface and the third surface in the firstdirection or is arranged between the third surface and the secondsurface in the first direction.
 12. A steering device comprising: asteering column having a configuration in which a front section of anouter column is set with respect to a rear section of an inner column sothat a relative displacement therebetween can be applied in an axialdirection, the inner column being arranged at a relatively front side,the outer column being arranged at a relatively rear side; a supportbracket including a pair of support plates which sandwich the frontsection of the outer column from both sides thereof in a widthdirection, the support bracket being installable on a vehicle body; andan adjusting rod inserted through a first through hole formed in thefront section of the outer column and second through holes formed in thesupport plates in the width direction, wherein a slit is formed in thefront section of the outer column and extends at least in the axialdirection of the outer column, a pair of clamp parts are each providedadjacent to the slit, in a circumferential direction and arranged onportions on both of the sides of the outer column in the width directionsuch that the clamp parts are bent when an interval between innersurfaces of the support plates is reduced to elastically sandwich anouter circumferential surface of the inner column, a pair of actingsurfaces are provided on both lateral surfaces of the outer column inthe width direction and are spaced apart from each other in a verticaldirection such that each of the clamp parts is arranged therebetween,and such that torque acting on the outer column via the acting surfacesis transmitted to inner surfaces of the support plates, end sections ofthe acting surfaces in a forward and rearward direction are continuousin the vertical direction via side surfaces, in the width direction, ofa pair of joining parts extending in the vertical direction, and theside surfaces, in the width direction, of the joining parts are offsetinwardly from the acting surfaces in the width direction.
 13. A steeringdevice comprising: a steering column including an outer column and aninner column, a part of the inner column being enclosed by the outercolumn; a support bracket attachable to a vehicle body to support thesteering column; and a tightening mechanism having a first state inwhich the steering column is tightened with the support bracket and asecond state in which the tightening is released, wherein the outercolumn includes: a first surface and a second surface arranged spacedapart from each other in a first direction, which intersects an axialdirection, and such that the first surface and the second surface arepressed by the support bracket in the first state; and a clamp parthaving a third surface, the third surface being provided independentlyfrom the first surface and the second surface, and such that the thirdsurface is pressed by the support bracket in the first state, whereinthe first surface is located inside, in the first direction, a contourof the inner column, the second surface is located outside, in the firstdirection, the contour of the inner column, and the outer column furtherincludes a reinforcing part, an end portion of which is arrangedadjacent the second surface, and such that the reinforcing part isbridged between both sides of the outer column in a second direction,which intersects the axial direction and the first direction, thereinforcing part being arranged between the second surface and the thirdsurface in the first direction.
 14. A steering device comprising: asteering column including an outer column and an inner column, a part ofthe inner column being enclosed by the outer column; a support bracketattachable to a vehicle body to support the steering column; and atightening mechanism having a first state in which the steering columnis tightened with the support bracket and a second state in which thetightening is released, wherein the outer column includes: a firstsurface and a second surface arranged spaced apart from each other in afirst direction, which intersects an axial direction, and such that thefirst surface and the second surface are pressed by the support bracketin the first state; and a clamp part having a third surface, the thirdsurface being provided independently from the first surface and thesecond surface, and such that the third surface is pressed by thesupport bracket in the first state, acting surfaces each including thefirst surface and the second surface are provided on both sides of theouter column in a second direction, which intersects with the axialdirection and the first direction, end sections of the acting surfacesin the axial direction are continuous in the first direction via sidesurfaces, in the second direction, of a pair of joining parts extendingin the first direction, and the side surfaces, in the second direction,of the joining parts are offset inwardly from the acting surfaces in thesecond direction.
 15. A steering device comprising: a steering columnincluding an outer column and an inner column, a part of the innercolumn being enclosed by the outer column; a support bracket attachableto a vehicle body to support the steering column; and a tighteningmechanism having a first state in which the steering column is tightenedwith the support bracket and a second state in which the tightening isreleased, wherein the outer column includes: a first surface and asecond surface arranged spaced apart from each other in a firstdirection, which intersects an axial direction, and such that the firstsurface and the second surface are pressed by the support bracket in thefirst state; and a clamp part having a third surface, the third surfacebeing provided independently from the first surface and the secondsurface, and such that the third surface is pressed by the supportbracket in the first state, wherein the outer column further has afourth surface that is provided independently from the first surface,the second surface, and the third surface, and in the second state, agap corresponding to an amount of tightening by the tightening mechanismis provided between the third surface and the fourth surface in a seconddirection, which intersects with the axial direction and the firstdirection.